Phil: New location, it got cold again. Hey guys, it’s Phil from smilinggardener.com. If you haven’t picked up my free online gardening course, you could do that right on the Home page of smilinggardener.com. Today we’re talking about cover crops for garden.
The least expensive organic fertilizer in the world is cover crops because just for a little bit of seed, which costs hardly anything you can do your whole garden and there are a lot of fertility benefits to cover cropping. So what a cover crop is, is when you plant some seed out into your garden, usually during the offseason when you don’t have any vegetables or anything else growing and you’re doing for various reasons but usually to improve the health of the soil and of the garden in general.
Cover crops have a lot of benefits. One of the main ones I often think about is with fertility. If you were to leave your bed without any plants in it over the winter, it will lose a lot of nutrition especially if you get a lot of rain during fall, winter, spring, but if you have a cover crop in there, it’s going to retain those nutrients up into itself and then we’re going to return that cover crop to the soil in some way and so those nutrients are going to stay there. Likewise, it’s also increasing fertility by getting nutrients out of the soil.
The next one is weed and pet control, which I was talking about a couple of weeks ago. With weed control, just by having a crop there that densely covers your soil, it’s going to shade out and crowd out a lot of weeds from starting in the fall and again in the spring, but also many cover crops exude these compounds, we call them allelopathic compounds; basically these toxins that stop other seeds from germinating, so it controls weeds that way. Then with predators, there are many different ways, probably through some compounds that it exudes, they’re going to control some predators but also by attracting beneficial insects into your garden and the last one is with organic matter.
A cover crop is photosynthesizing and becoming big and taking in carbon and we’re going to return that carbon to the soil, it’s going to be organic matter. So there’s a lot of fertility increases with cover cropping. So there are many benefits of cover crops. I just listed some of the main ones there and really, they just are about improving our soil and improving plant health, improving garden health.
What I want to do now is list the two different main kinds of cover crops which are legumes and grasses. So legumes are nitrogen-fixing plants, which means, they house these little bacteria on their roots and those bacteria can take nitrogen out of the air and turn it into nitrogen that can be taken up by plants. So they will use a lot of that nitrogen on their own. They may give a little bit up to the soil while they’re growing, but mostly it’s when we turn those cover crops in or do something with them before they’ve gone to seed that that nitrogen gets put back into the soil.
One of my favorites is called vetch, which you can kind of see over here and which I’ll hold up to the camera. It’s like this and it grows kind of like almost like a vine. It really grows around and it will grow up any kind of trellis or any kind of other grass that might be around it and it’s a really good nitrogen producer. It’s one of the best in terms of making a lot of nitrogen. This is a red clover, an annual clover that is another good nitrogen producer. A white clover is often a perennial clover and it will be used – it could be used in a lawn or it could be used in an orchard, as a crop it’s going to come back every year and continue to produce nitrogen.
It’s starting to rain here a little bit. Now we’re on to grasses. What I really like about grasses is that they grow big and fast. They create a lot of organic matter for the soil, they control weeds really well because they grow really big and fast and also because they exude these allelopathic compounds into the soil and they also are really good at holding nitrogen and other nutrients in the soil, whereas clover is about creating the nitrogen, the grasses more are really good at holding that nitrogen and keeping it from leaching out.
Two of the main grasses are cereal rye and annual ryegrass. And they’re both know for having these toxins that are really good at controlling weeds and they’re just very commonly used throughout much of North America. There are others, I really enjoy oats. I really love oats. They’re great for climate like mine, it’s colder and wetter. There are many others.
So the cover crop usually goes into the soil late in the summer or early fall, gives a little bit of time to establish before winter and then it will really grow a lot in the spring before we deal with it in the spring. When it comes the time to decide what you’re going to plant, there’s often going to be some local knowledge for your area. The farmers will know, but really what you need to do is just go to your – do a little research online or go to your local garden center and they’re going to have crops that are appropriate hopefully. It doesn’t matter that much. That’s why I always say – just pick something and get some kind of crop always covering your soil. What I like to do is mix a legume and a grass and then I get the benefits of both.
So I might do a rye with a vetch, or a clover with an oats, and when spring time comes, those crops are going to start growing again and you want to figure out when you’re going to be planting into your soil which you should always wait for that because we get these late cold spells like we’re having right now and I’m glad I haven’t planted anything in here yet, but what I would do is figure – and we’re going to work backwards and if I’m going to be seeding directly into the soil, a few weeks before that, I want to take out the cover crop.
Now farmers will use herbicides for this if they’re conventional farmers. Organic farmers will use some kind of a plough and what organic gardeners will use is this trusty old thing we used to get weeds to, which is a hoe and what you do is just hoe them down – hoe down, hoe them down just like you would a weed, maybe lightly incorporate them into the soil.
I’m not a fan of tilling too much, but if I just lightly incorporate them into the top of the soil, they’re going to break down faster and they’re going to retain more nutrition, especially nitrogen as less of it is going to be leached if I can lightly incorporate it. Some of it can be left as a mulch too and if you have too much or for some reason you don’t want it to be a mulch, you can move it over into a compost pit and that’s fine too. So it’s just like this. And even just by hoeing it kind of incorporates a fair amount; gets a little soil on top of it.
If you have any questions about cover crops for your garden, you can ask me down below and I’ll answer. If you haven’t signed up for my free online organic gardening course, you can do that down below. You can also join me on Facebook at facebook.com/smilinggardener. Phil out.
Reduce nutrient leaching, increase fertility and increase organic matter without the added expense of bringing in fertilizers and organic matter,
Control weeds and plant predators without every spraying a pesticide, as well as attracting beneficial insects and microbes without ever bringing in earthworms or ladybugs,
Prevent erosion, break up compacted soil, improve both drainage and water retention, all without rototillers or compost or buying mulch
This is a small patch of clover and vetch I’ve let stay through the summer.
…And much more. Healthier soil, less work – what’s not to like?
The most common types of cover crops are legumes and grasses…
Legume Cover Crops
Legumes host nitrogen-fixing bacteria in their root nodules.
Fortunately, they contribute more nitrogen than they need for their own use, especially when they’re chopped down before going to seed.
Then their roots and leaves are allowed to decompose in the soil.
Some of the most popular overwintering legumes include vetch, various types of clover, fava beans, bird’s-food trefoil, cowpeas, and winter peas.
Which ones you use depends on your needs, but it’s most important just to pick one and roll with it.
Vetch has very high overall nitrogen production, while perennial white clover is a popular living mulch for use in orchards and ornamental gardens.
Red clover is often used as a dependable winter annual in eastern North America, while the tall and beautifully colored annual crimson clover is great for regenerating a fallow bed through summer in the west.
I’ve seen Austrian field peas, planted thickly in fall, completely displace persistent weeds in wildly overgrown beds. The peas sprout early in spring, shading the soil before the weeds have a chance to get going.
Grass Cover Crops
Grasses are great for creating lots of organic matter, controlling weeds, and reducing leaching of nitrogen and other nutrients.
They’re like chefs who can make a tasty and plentiful dish out of the leftover scraps.
They’re useful if your soil has a lot of nitrogen and other nutrients after harvest, because they’ll help prevent these nutrients from leaching away.
They also build humus effectively by growing fast and contributing cellulose and lignin.
Grasses are handy for their sheer exuberance – crowding out weeds with heaps of organic matter and by producing unfriendly root-zone “allelopathic” chemicals.
Because of those chemicals, it’s important to wait several weeks after removing the grass in spring before you seed vegetables.
High-carbon grasses take a lot longer than nitrogen-rich legumes to break down, though, so they may not be a great choice if your soil’s low in nitrogen, or if you need to plant in a hurry after turning in your garden cover crop.
The workhorses of winter cover crops for gardens are cereal rye and annual ryegrass. Oats can also be a good choice in areas with cold autumns and wet soil – they’re one of my favorites for my area.
Buckwheat, while not a true grass, is great for poor soils and for use in the shoulder season rather than over winter. And there are others, like barley, sorghum, and winter wheat.
Choosing Cover Crops For Gardens
I always try to mix a grass and legume – this is clover and oats (and garlic peaking through).
Among the many cover crops for gardens that are available, certain species and combinations are universally popular.
You’ll find that growers in your area may favor particular plants or grass-legume pairings, such as rye and vetch.
For home gardeners, the best way to select a cover crop is often to try a mix rather than choosing just one.
That way something should do well, whatever weather and soil conditions you have.
If you start with the basics, you can follow up on success by experimenting.
When to plant cover crops? I usually sow my cover crop seed in late summer/early fall so it can establish a little bit before winter. Then it will take off in spring.
Harvesting The Cover Crop
Cover crops for vegetable gardens are removed a few weeks before it’s time to seed, and usually at least a week before you transplant.
Giving the soil a few weeks to rest before you plant allows the cover crops to begin releasing nitrogen into the soil, and gives the allelopathic chemicals released by grass roots time to break down.
You’ll want to hoe down (I don’t mean the folk dance) most of your cover crop.
It’s best to incorporate it lightly into the top few inches of soil and leave some of it as a mulch, or second best would be to move it to the compost bin.
Farmers mostly use herbicides to kill the crop, but we’re trying to support the life in our gardens rather than kill it, so it’s worth relying on somewhat more labor-intensive tools like the hoe.
Any questions about cover crops for gardens? Or what do you use? Let me know below!
I am new to the smiling gardener way of gardening but In just one month I have seen amazing results!Thanks for sharing
Cool!
I’ve been considering using cover crops in my vegetable garden for awhile now. It’s so hard to imagine sowing what most would consider weeds into my veggie patch. I have seeded my lawn with clover already and the results are good. This maybe the push I need to try it. Are all of these hardy to zone 4, or should I rule some out?
For grasses, cereal rye and wheat are hardy. Not annual ryegrass or oats. For legumes, both hairy vetch and red clover are hardy for you. Good luck!
This is my first year with this garden space and low and behold, it is almost pure clay! We had no idea how much until we planted it and it rained and dried. Hardly anything came up, except the beans and squash varieties. Forget the carrots, lettuce, and other delicate seedlings. We’ve heard about cover crops and lime helping to eradicate the clay, gradually. WE do composting, but our current volume isn’t sufficient to make a dent in the whole garden. We did use it to plant the tomatoes and peppers and they are doing great! What do you suggest for the garden as a whole? I live in WNY, south of Buffalo. HELP! :-/
Hi Susan, I also live in the Buffalo area and can understand what you are going through. I suggest you contact the Cornell Co-operative Extension’s Master Gardener’s Hotline. They can give you a lot of suggestions on how to deal with clay soil. For starters, you want to get as much organic material as possible into your soil; compost, leaf mulch, peat moss etc. You can call around to the local nurseries to get more compost.
Oops, I didn’t see this comment from Phyllis before I responded. I agree that organic matter will help, but if you use too much compost/manure, you’re probably going to be adding a lot of potassium, which will further compact the soil. A little compost is great, but more important in my opinion is balancing out the soil nutrient ratios based on a quality soil test.
Thanks, Phyllis! Cornell it is!!! Susan 🙂
Clay actually has benefits, such as being able to hold many more nutrients than sandy soil. So it’s a pretty nice thing to have in the long run. Yes, compost will gradually help as will mulching and cover crops. But also, you really should get a soil test with an organic soil lab and follow their recommendations. That may include lime, but their recommendations will tell you which lime you need (probably not dolomite) and which other fertilizers. Balancing out the soil nutrients is critical to relieving compaction. Last is to improve the soil food web with things like aerated compost tea and effective microorganisms.
Thanks, PhilAS usual, it takes a master gardener to take all of the ‘possible’ remedies and sort through them to find the best solution! I will send a soil sample to Cornell to see what specific suggestions they have for my garden! Thanks again for providing a forum for others to share their ideas and for getting back to me yourself! I really appreciate it! As for the garden and this year’s crops? Well, as my gardening partner keeps saying, “It will be better next year!”Oh, one more question. You mentioned dual cover drops. I feed the birds, inside and out, and millet is a favorite. The seeds sprout easily and those that end up in my potted plants (I recycle my canary’s contaminated water by using it to water houseplants) come up as a grass like plant. Could I plant millet as a cover crop in my garden, harvest the seed heads, and then till in the rest in the spring? I would also plant red clover. Thanks again!
Yes, you can definitely use millet as a cover crop, although if you’re doing it for the seeds then it’s really more like a regular crop the 1st year – you’ll harvest the seeds in late summer and then probably turn the crop in the following spring.P.S. My preference is to use a soil lab that gives organic recommendations: https://www.smilinggardener.com/organic-soil-management/soil-testing-labs/
Thank you Phil. I live in the eastern foothills of San Jose where we don’t get any rain in the summertime. Would I have to irrigate to use these cover crops or are any drought tolerant?
Some are very tolerant of drought. For grasses, Sorghum–sudan and Barley. For legumes, Sweetclovers and Cowpeas.
Good job! This article about green fertilizer plants for garden building has inspired me to mix legume seeds with my Abruzzi rye cover this fall.
Beauty!
Cover crops for southwest Florida…have any ideas for me?
Legumes – crimson or berseem clover are great down there.Grasses – cereal rye and sorghum-sudangrass are great, too.
Thanks Phil for getting back to me about using millet as a cover crop! I’ll have to look up an organic soil lab to use for my soil sample! I sure feel special having thee ‘Smiling Gardener’ answering my questions! I certainly appreciate it! 🙂
I have some areas in my front and back yard that need to be covered. would a cover crop be a good idea? if so, what is the best combo that will last all year (not to be tilled). Thnx!I live in Sacramento California – zone 14 and 9
One suggestion is a perennial white clover and a perennial ryegrass. They’ll keep coming back year after year. Or get annual versions if you don’t want them back next year.
What cover crops would you recommend for dense shade areas? This is for permanent cover, not a vegetable garden, so I know pachysandra works well in flower beds. Are there any types of clover that tolerate shade that I could add to my turf grass? Thanks!
I don’t know of any traditional cover crops that tolerate dense shade, but many of the common clovers (like white, red, crimson) will take quite a bit of shade. A perennial white clover would be worth trying.
Great post! Do you think it’s possible to sow vegetables directly in the cover, keeping it alive, as some do in the Pasture Cropping system for grain on perennial pastures?
Sure, it’s definitely possible, but it depends on the cover crop being used and the vegetables being sown. For example, a think cover crop of grass generally won’t allow much of any seedling to come up through it, but if you have a sparse cover crop of clover (which may mean you would remove some of the clover), there are lots of vegetables that would probably grow well with that.
Great. That’s what I want to experiment in some bed of my garden this spring. I’ve sown a mix of clover, vetch and forage turnips, In theory, with help of gypsum, mycorriza and cow’s manure biofertilizer, enventually (maybe not the first year) the cover will get their roots enough deep into the subsoil, so it won’t compete with the crops roots (that will be feeding on the first 20 cm or so), but it will help keeping great soil structure, pump up nutrients from below, and acting as a kind of living mulching. The idea is to “razor” this cover superficially in key moments (like the sprouting of the vegetable, and anytime the cover is about to flower). I’m excited for trying it! I guess it can work with cucurbits, which are vigourous plants?
So sorry for my poor english 🙂
It can work with curcurbits as long as you keep the cover crops under control. Careful about adding too much gypsum at the same time as microbes such as mycorrhizal fungi, because it might be possible that the sulfur will harm the microbes. I’m not sure if that would be the case for the fungi, but it is the case for some microbes. Sounds like a fun experiment!
Well, I’m blown away. Vetch has been my nemesis for nine years, and it is gradually winning. I could not believe the video shots that showed, clearly, that my enemy is what you are touting as a garden cover. All I need to do is put my hoe away, sit on the porch and watch it take over! Happy birthday and Merry Christmas to me! Who would have thought a weed that has defied my every destructive effort (including RoundUp one year–killed large patches of my lawn but the vetch marched on) would be welcome at court. I have to go and lie down. Unbelievable. Thank you (I think).
I have a few questions: First, what do you think about buckwheat as a grass cover crop (I live in zone 4)? Second, I’m not finished with my garden by early fall. My kale produces until December, and I like to leave the carrots in until then as well. Plus, I’d like a late crop of radishes, and then there’s the winter squash that can go until November. Basically I want to keep my eatables going as long as possible, and that doesn’t give time for any cover crop to get going. Should I plant the cover crops around the things I still have going? I have a 12′ x 16′ raised bed for my garden. And third, instead of hoeing the cover crop under, could I just put more compost on top and bury it? I mean, hoeing a foot high raised bed would be pretty awkward. And since the soil in raised beds tends to settle each year, it does need to be replenished.
Hi Anne, buckwheat can make a great cover crop. It won’t survive the winter, but works well in spring/summer/fall as a cover.Cover crops are often sown before the preceding crops are harvested, but usually only a couple of weeks, so in your situation, you’re going to want to keep them separate. That is a fairly common decision to face. I often leave the remnants of my plants – even things like tomatoes – rather than sowing a cover, and only sow a cover in the bare areas.Buckwheat will be killed over the winter, so you won’t have to hoe it. But even with other covers, covering with compost isn’t a great option because it would require too much compost, and even then, the cover might find it’s way through. Compost plays an important part in the garden, but there is such a thing as too much. We want to have more soil than compost, even in a raised bed.
Thanks a lot for your reply to my question, Phil. You say that we want to have more soil than compost, but how does this work in a raised bed where I didn’t dig up any dirt and so don’t have regular soil from the ground for that? Should I buy a truckload of topsoil from a nursery or… ?
Yes, my suggestion is to bring in soil or use some from your property (you could put a pond in the hole, or something else). Sometimes things do grow well in straight compost, but sometimes not. It partially depends on the quality of the compost, but in my view, it’s not a great solution overall. It keeps shrinking even after it’s been aged awhile, often doesn’t drain all that well, and can cause some plants to grow poorly. I do encourage you to try it for a year or two and see how it goes, but if you run into issues, a mix may be in order.
I,m thinking about planting some flax but know little about it. Can you give some pointers? I live in NYS and have clay soil which I,m trying build up by composting.
We have an electric cultivator – a light duty rototiller. I assume it could be used to till the cover crop into the top inch of the garden soil – BUT as a chiropractor I recommend the hoe.Using a hoe to incorporate a cover crop is an IDEAL exercise for sedentary North Americans whose standard posture is seated, arms and shoulders forward. Hoeing works the muscles of the upper back, shoulders and abdominal muscles particularly. It greatly improves posture and the function of internal organs, as well as core strength and fitness. In addition, it is a simple, repetitive, meditative activity that clears the mind and stimulates creative thought and problem solving.So hoe, hoe, hoe – merry crispness!
Excellent info–and funny, too! Thanks.
Thanks for sharing!
When you remove the cover crop in preparation for planting the veggies, I am assuming you do not want to remove the roots. Or do you? When hoeing, do you just break up the dirt and try to push the crop growing on top into it somehow? Seems like it would be very hard to get the surface growth pushed into the soil without puling it up by the roots first.
Since we’re not using herbicides to kill the crop, we do want to get in there with a hoe to kill the upper roots. Some plants such as cereal rye will re-sprout, so you definitely want to get the roots then. When I’m done hoeing, my cover is partially buried (which helps it break down faster), and partially on the surface (which keeps it as a mulch). It’s either more buried or less buried depending on my goals for it (e.g. if I want to sow seed in 3 weeks, I want to bury it to get it broken down, whereas if I want to keep it as a mulch, I don’t want to bury it so much).
Thanks so much, Phil. I have been conflicted for a long time re my need to break up my super clay content soil as opposed to leaving roots intact to not disturb the underground biologic activity nourishing the soil. I often see a network of fine roots interlaced in the soil up to about 10 inches down, but I cannot grow anything in the near concrete consistency of the clay unless I first break it up well and then add a big handful of potting soil to the spot I plant each seed to at least give them a fighting chance to get a plant started. If I am planting a lot of plants, I dig out a thinnish row about 4 inches deep and put about two inches of potting soil in, mixed then with the clay soil, to give the adjacent plants some reasonably soft space to grow into before they encounter the hard pack clay bearing soil. My Much of my squash is quite stunted because the plants get started, and then the clay is just too much for them to overcome. I get a small amount of squash from them, but nothing like the crop I should be getting, especially considering all the work I put into encouraging them. I’d appreciate any tips for clay clod busting that is sustained after the plants are in and have been watered for over a month; for that compacts the soil again.
The long term solution to breaking up clay is: increasing soil organic matter content (compost, mulch, cover crops), biological diversity (compost and microbial inoculants) and nutrient balance (with soil testing and subsequent strategic fertilizing). A lot of organic gardeners rely only on the organic matter, but if we’re trying to grow specific plants in a soil that wouldn’t otherwise grow those plants, we need to improve the soil’s biology and chemistry rather than just focusing on the physics. Potting soil doesn’t do much of anything to get us there. Nutrient balancing does take time, but that, along with improving the biology, is the long-term sustainable solution to breaking up those clods.
what would be a good cover crop for zone 9b. i don’t want to use clover as i have cats and hear it is poisonous for cats and some of the crops suggested i believe are for cooler weather.thanks
If you want to stick with a legume, a vetch could be nice for you, or a winter pea.
Hey Phil,I’ve been reading your posts for about a year now, as I am a new gardener trying to learn everything I can about the organic method. I’ve had a garden for about two years now, and am constantly learning and changing things. I’m writing because I’m having a gardening crisis, and was wondering if you might have advice for me. To make a long story short, last week I had a pesticide company spray for wasps because they were getting into my kids bedrooms (only the second time I’ve ever used a company like this, and for the same reason), and before I could speak to the technician, he treated my yard as well. I was eating breakfast, looked out the window and saw Mr. technician innocently throwing handful after handful of pesticide granules all over the yard, walking through my organic garden, throwing handfuls of poison all over my garden like it was confetti. I shrieked nooooooo running to the window, and realizing it was too late, sat dumbfounded all day trying to figure out what to do. I researched the chemical I think it was, and the website says to keep it away from food and if you have to use it in a vegetable garden, only use it in trays so that it doesn’t come in contact with the plants. Now I don’t know what to do. At the most productive time for my garden, I feel like I can’t eat anything from it because it’s contaminated. Do you have any advice?Thank you so much for your time,Kate
Hi Kate, sorry for your troubles. Not knowing anything about the specific chemical that was sprayed, I can share with you my general feelings about pesticides. Do I like to eat food that’s been treated with them? No, of course not. Do I do it sometimes? Yes, absolutely. Some organic food items are so expensive that I buy conventional instead, especially when the conventional seems to be more nutrient-dense, which is sometimes the case. So with these granules, which weren’t even applied to the plants directly, I would probably still eat the food. I might not eat my root vegetables, but I’d probably eat my fruiting vegetables like tomatoes, and also my herbs. Of course I’d wash them like crazy, and if the chemical in question is especially toxic, I’d have to re-evaluate, but the fact is that chemicals are a part of our world, and while I avoid them as much as possible, they’re going to be there sometimes. You’ll have to figure out what feels right to you in your situation, but those are my thoughts.
Thanks, Phil. That’s excellent advice for ALL of us!!
Thank you so much for your input. I appreciate you taking the time to respond. I’m still not sure about what I will do. I think I’ve become emotionally attached to my garden, and maybe am not being completely rational about it. I’m working on some ideas for how to improve things for next year, and am excited about that. I guess the looming decision is just what to do for the next couple of months. Thanks again for your thoughts.
I was thinking about just burying my cover crops with the compost I am making during the winter.
Yes, you can certainly incorporate them into your compost.
I live in New Zealand and Spring is recognized from September the first. I have a cover crop of mustard in my vegetable garden and when I turn
it in how deep should I bury it and how long after should I wait before putting potatoes in the ground and subsequently sowing seeds such as
beans, onions, carrots, tomato plants etc.? Gordon
If you want to bury it, do so just enough to get soil contact with the plants. You don’t want to bury it too deeply because that can lead to some issues. I would plant potatoes 2 weeks later and sow seeds 4-8 weeks later, depending on how fast the crop breaks down.
So much AMAZING information. Thank you, Phil!!
And just to be clear, because I am a bit confused—plant or sow seeds of cover crops in fall. They’ll grow in winter? Or is it that they’ll grow in late fall and they’ll start decomposing in winter? I’m not real clear for some reason. You’ve explained it fantastically, it’s just my comprehension I guess.
Also—with hoeing and turning the crops into the soil a few inches, this doesn’t disrupt the fungi and microbes? Or it does, but not so much because it’s not into the depths of the soil?
Thank you, Phil
You sow the seeds in early fall, they grow for a couple of months and then they don’t grow over the winter, but do good things for the soil anyway. Yes, turning the crops in does harm some soil biology – not as much as deep tilling, but some – but it also provides many benefits to the soil, so it’s a worthwhile trade-off.
Perfect!
“The breeze at dawn has secrets to tell. Don’t go back to sleep.”
~Rumi
For the second year in a row, I am growing a Living Mulch (cover crop) of Crimson Clover with the peppers. I have a raised bed with 18 pepper plants, and after they were successfully transplanted and growing I sowed inoculated Crimson Clover seed and raked it into the ground. The clover is just now getting its first true leaves, but is already providing good ground cover. Last year the clover grew beautifully, and provided a great living mulch until the pepper plants grew so much that they created a heavy canopy of shade. The Crimson Clover died after the shade got too heavy, but the fallen leaves continued to provide a good mulch for the rest of the summer. In the fall, after the peppers were killed by frost I cut off the pepper plants at the soil level and sowed Winter Rye for the winter cover crop. It worked so well in that bed last year, that I am trying the same technique in another bed with peppers again.
Very nice. Thanks for sharing!
I live in los Angeles and have just pulled out my summer garden. I have 8 raised beds.I am going to sow a cover crop for the winter, but wanted to know if I need to prepare the soil in any way.
Thanks
Diane
No, as long as the soil isn’t too compacted and you slighly bury most of the seed, even with just a rake (just 1/4″ deep is all you need), and then keep them watered, you should be good.
Thanks for getting back to me. I love your site and recommend it to all my gardening friends!
I’ve had the worst season ever. Bacterial wilt,aphids and squash bugs. Can you suggest a cover crop to help me out.
I am new to the smiling gardener way of gardening but In just one month I have seen amazing results!Thanks for sharing
Cool!
I’ve been considering using cover crops in my vegetable garden for awhile now. It’s so hard to imagine sowing what most would consider weeds into my veggie patch. I have seeded my lawn with clover already and the results are good. This maybe the push I need to try it. Are all of these hardy to zone 4, or should I rule some out?
For grasses, cereal rye and wheat are hardy. Not annual ryegrass or oats. For legumes, both hairy vetch and red clover are hardy for you. Good luck!
This is my first year with this garden space and low and behold, it is almost pure clay! We had no idea how much until we planted it and it rained and dried. Hardly anything came up, except the beans and squash varieties. Forget the carrots, lettuce, and other delicate seedlings. We’ve heard about cover crops and lime helping to eradicate the clay, gradually. WE do composting, but our current volume isn’t sufficient to make a dent in the whole garden. We did use it to plant the tomatoes and peppers and they are doing great! What do you suggest for the garden as a whole? I live in WNY, south of Buffalo. HELP! :-/
Hi Susan, I also live in the Buffalo area and can understand what you are going through. I suggest you contact the Cornell Co-operative Extension’s Master Gardener’s Hotline. They can give you a lot of suggestions on how to deal with clay soil. For starters, you want to get as much organic material as possible into your soil; compost, leaf mulch, peat moss etc. You can call around to the local nurseries to get more compost.
Oops, I didn’t see this comment from Phyllis before I responded. I agree that organic matter will help, but if you use too much compost/manure, you’re probably going to be adding a lot of potassium, which will further compact the soil. A little compost is great, but more important in my opinion is balancing out the soil nutrient ratios based on a quality soil test.
Thanks, Phyllis! Cornell it is!!! Susan 🙂
Clay actually has benefits, such as being able to hold many more nutrients than sandy soil. So it’s a pretty nice thing to have in the long run. Yes, compost will gradually help as will mulching and cover crops. But also, you really should get a soil test with an organic soil lab and follow their recommendations. That may include lime, but their recommendations will tell you which lime you need (probably not dolomite) and which other fertilizers. Balancing out the soil nutrients is critical to relieving compaction. Last is to improve the soil food web with things like aerated compost tea and effective microorganisms.
Thanks, PhilAS usual, it takes a master gardener to take all of the ‘possible’ remedies and sort through them to find the best solution! I will send a soil sample to Cornell to see what specific suggestions they have for my garden! Thanks again for providing a forum for others to share their ideas and for getting back to me yourself! I really appreciate it! As for the garden and this year’s crops? Well, as my gardening partner keeps saying, “It will be better next year!”Oh, one more question. You mentioned dual cover drops. I feed the birds, inside and out, and millet is a favorite. The seeds sprout easily and those that end up in my potted plants (I recycle my canary’s contaminated water by using it to water houseplants) come up as a grass like plant. Could I plant millet as a cover crop in my garden, harvest the seed heads, and then till in the rest in the spring? I would also plant red clover. Thanks again!
Yes, you can definitely use millet as a cover crop, although if you’re doing it for the seeds then it’s really more like a regular crop the 1st year – you’ll harvest the seeds in late summer and then probably turn the crop in the following spring.P.S. My preference is to use a soil lab that gives organic recommendations: https://www.smilinggardener.com/organic-soil-management/soil-testing-labs/
Thank you Phil. I live in the eastern foothills of San Jose where we don’t get any rain in the summertime. Would I have to irrigate to use these cover crops or are any drought tolerant?
Some are very tolerant of drought. For grasses, Sorghum–sudan and Barley. For legumes, Sweetclovers and Cowpeas.
Good job! This article about green fertilizer plants for garden building has inspired me to mix legume seeds with my Abruzzi rye cover this fall.
Beauty!
Cover crops for southwest Florida…have any ideas for me?
Legumes – crimson or berseem clover are great down there.Grasses – cereal rye and sorghum-sudangrass are great, too.
Thanks Phil for getting back to me about using millet as a cover crop! I’ll have to look up an organic soil lab to use for my soil sample! I sure feel special having thee ‘Smiling Gardener’ answering my questions! I certainly appreciate it! 🙂
I have some areas in my front and back yard that need to be covered. would a cover crop be a good idea? if so, what is the best combo that will last all year (not to be tilled). Thnx!I live in Sacramento California – zone 14 and 9
One suggestion is a perennial white clover and a perennial ryegrass. They’ll keep coming back year after year. Or get annual versions if you don’t want them back next year.
What cover crops would you recommend for dense shade areas? This is for permanent cover, not a vegetable garden, so I know pachysandra works well in flower beds. Are there any types of clover that tolerate shade that I could add to my turf grass? Thanks!
I don’t know of any traditional cover crops that tolerate dense shade, but many of the common clovers (like white, red, crimson) will take quite a bit of shade. A perennial white clover would be worth trying.
Great post! Do you think it’s possible to sow vegetables directly in the cover, keeping it alive, as some do in the Pasture Cropping system for grain on perennial pastures?
Sure, it’s definitely possible, but it depends on the cover crop being used and the vegetables being sown. For example, a think cover crop of grass generally won’t allow much of any seedling to come up through it, but if you have a sparse cover crop of clover (which may mean you would remove some of the clover), there are lots of vegetables that would probably grow well with that.
Great. That’s what I want to experiment in some bed of my garden this spring. I’ve sown a mix of clover, vetch and forage turnips, In theory, with help of gypsum, mycorriza and cow’s manure biofertilizer, enventually (maybe not the first year) the cover will get their roots enough deep into the subsoil, so it won’t compete with the crops roots (that will be feeding on the first 20 cm or so), but it will help keeping great soil structure, pump up nutrients from below, and acting as a kind of living mulching. The idea is to “razor” this cover superficially in key moments (like the sprouting of the vegetable, and anytime the cover is about to flower). I’m excited for trying it! I guess it can work with cucurbits, which are vigourous plants?
So sorry for my poor english 🙂
It can work with curcurbits as long as you keep the cover crops under control. Careful about adding too much gypsum at the same time as microbes such as mycorrhizal fungi, because it might be possible that the sulfur will harm the microbes. I’m not sure if that would be the case for the fungi, but it is the case for some microbes. Sounds like a fun experiment!
Well, I’m blown away. Vetch has been my nemesis for nine years, and it is gradually winning. I could not believe the video shots that showed, clearly, that my enemy is what you are touting as a garden cover. All I need to do is put my hoe away, sit on the porch and watch it take over! Happy birthday and Merry Christmas to me! Who would have thought a weed that has defied my every destructive effort (including RoundUp one year–killed large patches of my lawn but the vetch marched on) would be welcome at court. I have to go and lie down. Unbelievable. Thank you (I think).
I have a few questions: First, what do you think about buckwheat as a grass cover crop (I live in zone 4)? Second, I’m not finished with my garden by early fall. My kale produces until December, and I like to leave the carrots in until then as well. Plus, I’d like a late crop of radishes, and then there’s the winter squash that can go until November. Basically I want to keep my eatables going as long as possible, and that doesn’t give time for any cover crop to get going. Should I plant the cover crops around the things I still have going? I have a 12′ x 16′ raised bed for my garden. And third, instead of hoeing the cover crop under, could I just put more compost on top and bury it? I mean, hoeing a foot high raised bed would be pretty awkward. And since the soil in raised beds tends to settle each year, it does need to be replenished.
Hi Anne, buckwheat can make a great cover crop. It won’t survive the winter, but works well in spring/summer/fall as a cover.Cover crops are often sown before the preceding crops are harvested, but usually only a couple of weeks, so in your situation, you’re going to want to keep them separate. That is a fairly common decision to face. I often leave the remnants of my plants – even things like tomatoes – rather than sowing a cover, and only sow a cover in the bare areas.Buckwheat will be killed over the winter, so you won’t have to hoe it. But even with other covers, covering with compost isn’t a great option because it would require too much compost, and even then, the cover might find it’s way through. Compost plays an important part in the garden, but there is such a thing as too much. We want to have more soil than compost, even in a raised bed.
Thanks a lot for your reply to my question, Phil. You say that we want to have more soil than compost, but how does this work in a raised bed where I didn’t dig up any dirt and so don’t have regular soil from the ground for that? Should I buy a truckload of topsoil from a nursery or… ?
Yes, my suggestion is to bring in soil or use some from your property (you could put a pond in the hole, or something else). Sometimes things do grow well in straight compost, but sometimes not. It partially depends on the quality of the compost, but in my view, it’s not a great solution overall. It keeps shrinking even after it’s been aged awhile, often doesn’t drain all that well, and can cause some plants to grow poorly. I do encourage you to try it for a year or two and see how it goes, but if you run into issues, a mix may be in order.
I,m thinking about planting some flax but know little about it. Can you give some pointers? I live in NYS and have clay soil which I,m trying build up by composting.
Hi Jim, I think since this is such a potentially big topic, rather than reinvent the wheel, I’ll direct you to this nice little intro to growing flax: http://www.motherearthliving.com/gardening/flax-growing-and-processing
We have an electric cultivator – a light duty rototiller. I assume it could be used to till the cover crop into the top inch of the garden soil – BUT as a chiropractor I recommend the hoe.Using a hoe to incorporate a cover crop is an IDEAL exercise for sedentary North Americans whose standard posture is seated, arms and shoulders forward. Hoeing works the muscles of the upper back, shoulders and abdominal muscles particularly. It greatly improves posture and the function of internal organs, as well as core strength and fitness. In addition, it is a simple, repetitive, meditative activity that clears the mind and stimulates creative thought and problem solving.So hoe, hoe, hoe – merry crispness!
Excellent info–and funny, too! Thanks.
Thanks for sharing!
When you remove the cover crop in preparation for planting the veggies, I am assuming you do not want to remove the roots. Or do you? When hoeing, do you just break up the dirt and try to push the crop growing on top into it somehow? Seems like it would be very hard to get the surface growth pushed into the soil without puling it up by the roots first.
Since we’re not using herbicides to kill the crop, we do want to get in there with a hoe to kill the upper roots. Some plants such as cereal rye will re-sprout, so you definitely want to get the roots then. When I’m done hoeing, my cover is partially buried (which helps it break down faster), and partially on the surface (which keeps it as a mulch). It’s either more buried or less buried depending on my goals for it (e.g. if I want to sow seed in 3 weeks, I want to bury it to get it broken down, whereas if I want to keep it as a mulch, I don’t want to bury it so much).
Thanks so much, Phil. I have been conflicted for a long time re my need to break up my super clay content soil as opposed to leaving roots intact to not disturb the underground biologic activity nourishing the soil. I often see a network of fine roots interlaced in the soil up to about 10 inches down, but I cannot grow anything in the near concrete consistency of the clay unless I first break it up well and then add a big handful of potting soil to the spot I plant each seed to at least give them a fighting chance to get a plant started. If I am planting a lot of plants, I dig out a thinnish row about 4 inches deep and put about two inches of potting soil in, mixed then with the clay soil, to give the adjacent plants some reasonably soft space to grow into before they encounter the hard pack clay bearing soil. My Much of my squash is quite stunted because the plants get started, and then the clay is just too much for them to overcome. I get a small amount of squash from them, but nothing like the crop I should be getting, especially considering all the work I put into encouraging them. I’d appreciate any tips for clay clod busting that is sustained after the plants are in and have been watered for over a month; for that compacts the soil again.
The long term solution to breaking up clay is: increasing soil organic matter content (compost, mulch, cover crops), biological diversity (compost and microbial inoculants) and nutrient balance (with soil testing and subsequent strategic fertilizing). A lot of organic gardeners rely only on the organic matter, but if we’re trying to grow specific plants in a soil that wouldn’t otherwise grow those plants, we need to improve the soil’s biology and chemistry rather than just focusing on the physics. Potting soil doesn’t do much of anything to get us there. Nutrient balancing does take time, but that, along with improving the biology, is the long-term sustainable solution to breaking up those clods.
what would be a good cover crop for zone 9b. i don’t want to use clover as i have cats and hear it is poisonous for cats and some of the crops suggested i believe are for cooler weather.thanks
If you want to stick with a legume, a vetch could be nice for you, or a winter pea.
Hey Phil,I’ve been reading your posts for about a year now, as I am a new gardener trying to learn everything I can about the organic method. I’ve had a garden for about two years now, and am constantly learning and changing things. I’m writing because I’m having a gardening crisis, and was wondering if you might have advice for me. To make a long story short, last week I had a pesticide company spray for wasps because they were getting into my kids bedrooms (only the second time I’ve ever used a company like this, and for the same reason), and before I could speak to the technician, he treated my yard as well. I was eating breakfast, looked out the window and saw Mr. technician innocently throwing handful after handful of pesticide granules all over the yard, walking through my organic garden, throwing handfuls of poison all over my garden like it was confetti. I shrieked nooooooo running to the window, and realizing it was too late, sat dumbfounded all day trying to figure out what to do. I researched the chemical I think it was, and the website says to keep it away from food and if you have to use it in a vegetable garden, only use it in trays so that it doesn’t come in contact with the plants. Now I don’t know what to do. At the most productive time for my garden, I feel like I can’t eat anything from it because it’s contaminated. Do you have any advice?Thank you so much for your time,Kate
Hi Kate, sorry for your troubles. Not knowing anything about the specific chemical that was sprayed, I can share with you my general feelings about pesticides. Do I like to eat food that’s been treated with them? No, of course not. Do I do it sometimes? Yes, absolutely. Some organic food items are so expensive that I buy conventional instead, especially when the conventional seems to be more nutrient-dense, which is sometimes the case. So with these granules, which weren’t even applied to the plants directly, I would probably still eat the food. I might not eat my root vegetables, but I’d probably eat my fruiting vegetables like tomatoes, and also my herbs. Of course I’d wash them like crazy, and if the chemical in question is especially toxic, I’d have to re-evaluate, but the fact is that chemicals are a part of our world, and while I avoid them as much as possible, they’re going to be there sometimes. You’ll have to figure out what feels right to you in your situation, but those are my thoughts.
Thanks, Phil. That’s excellent advice for ALL of us!!
Thank you so much for your input. I appreciate you taking the time to respond. I’m still not sure about what I will do. I think I’ve become emotionally attached to my garden, and maybe am not being completely rational about it. I’m working on some ideas for how to improve things for next year, and am excited about that. I guess the looming decision is just what to do for the next couple of months. Thanks again for your thoughts.
I was thinking about just burying my cover crops with the compost I am making during the winter.
Yes, you can certainly incorporate them into your compost.
I live in New Zealand and Spring is recognized from September the first. I have a cover crop of mustard in my vegetable garden and when I turn
it in how deep should I bury it and how long after should I wait before putting potatoes in the ground and subsequently sowing seeds such as
beans, onions, carrots, tomato plants etc.? Gordon
If you want to bury it, do so just enough to get soil contact with the plants. You don’t want to bury it too deeply because that can lead to some issues. I would plant potatoes 2 weeks later and sow seeds 4-8 weeks later, depending on how fast the crop breaks down.
So much AMAZING information. Thank you, Phil!!
And just to be clear, because I am a bit confused—plant or sow seeds of cover crops in fall. They’ll grow in winter? Or is it that they’ll grow in late fall and they’ll start decomposing in winter? I’m not real clear for some reason. You’ve explained it fantastically, it’s just my comprehension I guess.
Also—with hoeing and turning the crops into the soil a few inches, this doesn’t disrupt the fungi and microbes? Or it does, but not so much because it’s not into the depths of the soil?
Thank you, Phil
You sow the seeds in early fall, they grow for a couple of months and then they don’t grow over the winter, but do good things for the soil anyway. Yes, turning the crops in does harm some soil biology – not as much as deep tilling, but some – but it also provides many benefits to the soil, so it’s a worthwhile trade-off.
Perfect!
“The breeze at dawn has secrets to tell. Don’t go back to sleep.”
~Rumi
For the second year in a row, I am growing a Living Mulch (cover crop) of Crimson Clover with the peppers. I have a raised bed with 18 pepper plants, and after they were successfully transplanted and growing I sowed inoculated Crimson Clover seed and raked it into the ground. The clover is just now getting its first true leaves, but is already providing good ground cover. Last year the clover grew beautifully, and provided a great living mulch until the pepper plants grew so much that they created a heavy canopy of shade. The Crimson Clover died after the shade got too heavy, but the fallen leaves continued to provide a good mulch for the rest of the summer. In the fall, after the peppers were killed by frost I cut off the pepper plants at the soil level and sowed Winter Rye for the winter cover crop. It worked so well in that bed last year, that I am trying the same technique in another bed with peppers again.
Very nice. Thanks for sharing!
I live in los Angeles and have just pulled out my summer garden. I have 8 raised beds.I am going to sow a cover crop for the winter, but wanted to know if I need to prepare the soil in any way.
Thanks
Diane
No, as long as the soil isn’t too compacted and you slighly bury most of the seed, even with just a rake (just 1/4″ deep is all you need), and then keep them watered, you should be good.
Thanks for getting back to me. I love your site and recommend it to all my gardening friends!
I’ve had the worst season ever. Bacterial wilt,aphids and squash bugs. Can you suggest a cover crop to help me out.
Where are you located?