You did a good job last fall getting cover crops planted. Now, they’ve taken over your garden and you don’t quite remember what you had planned to do with them. What you’ve done is to grow great biomass for your garden that you can use as compost material or cut down as mulch right where it was grown. Give yourself a pat on the back! The next step is to cut it down at the right time as mulch-in-place or cut it and put the material in the compost pile. At this stage it is all green matter and your compost would benefit from an addition of an equal amount, by volume, of dry, carbon material. At this time of year my carbon comes from Jerusalem artichoke stalks, or sorghum and cornstalks that I put aside in the fall. Maybe you have access to leaves, hay, or straw. If you are bringing in that material from outside sources, read my post Killer Compost to know what to look out for. Water well when building your compost pile.
Last May I wrote Cutting a Rye Cover Crop at Pollen Shed. It speaks to the importance of cutting your cover crop, in that case cereal rye, at the time when it has reached its most biomass, just before it produces viable seed. For any crop, that would be when it is flowering. You don’t normally think of grain crops with flowers, however, you will see where the seed heads begin to form and the pollen will be hanging off it. If you cut it earlier than that, the rye and wheat plants, like the grasses they are, will grow back. If you wait too long, seed will form. That’s okay if it’s seed you’re after. In that case, you would wait longer to cut it and need to make sure the seed has matured. One way to test is to cut a few seed heads and thresh out the seeds in your hand. If you don’t get seed that looks like what you planted, it’s not ready. After the plant has put its energy into seed production, it begins to die. You will see the rye and wheat plants begin to turn brown when it is time to harvest the seed. The harvest will be seed and straw and usually occurs here in mid-June.
Here in the Mid-Atlantic in zone 7 our last frost date is around April 26. Cereal rye is my major cover crop and generally sheds pollen around the end of the first week of May. That’s also about the time that the farmers who are on top of things are making their first cutting of hay. This year, however, the weather seems to be all mixed up. We didn’t have much of a winter and warm weather arrived early. Usually we have a spike in the temperature in the second week of April, fooling people into setting out their tomatoes, only to turn colder before the weather has settled. The weather did a good job convincing my rye that warm weather was here and it flowered early. I cut it in the beds where it would be left for mulch on April 20. I’m really interested to see how the rye and wheat do that are in the beds to be grown out for seed. The temperatures here dipped into the 30’s on April 24th and 25th after nighttime lows in the 60’s on April 16th and 17th. Looking back to my temperature records from last year, I see that the April nights were consistently warmer in 2011. Last year I cut the rye for mulch on May 10. It must be the lack of winter this year, not warm April nights that brought the rye to flower earlier in 2012. My video Cover Crops and Compost Crops IN Your Garden shows my management of this system.
It might be that you have grown Austrian winter peas or crimson clover as your cover crop. These crops are legumes which fix nitrogen from the air in the nodules on their roots, returning that nitrogen to the next crop as those roots decompose in the soil. You could cut these crops at flowering and let them lie as mulch, as with the rye, but their biomass wouldn’t be as long lasting as the rye. They are best used as green material for the compost, adding carbon to capture all the nutrients as composting occurs. Crimson clover, not to be confused with red clover, is a beautiful plant that generally flowers here around mid-April. The legumes can be easily pulled out or cut for compost material and the bed planted soon after. I wait two weeks to transplant after cutting the cereal rye beds for mulch, but I could transplant sooner than that into the legume-only beds. If I was seeding into the beds, I could easily do that in a legume bed two weeks after cutting. If I was only after the biomass and in a hurry to get the next crop in, I would cut crimson clover as soon as it has flowered. However, I have bees that enjoy it, so I wait a little longer before cutting so they can have the most benefit from the clover blooms.
Sometimes hairy vetch is planted in the fall to precede tomatoes. I’ve done that in two tomato beds this year. I prepared the beds last fall and moved the tomato trellises there at the same time. The vetch grew up and I cut it April 25. My tomatoes are ready now in the coldframe for planting out. I started the seeds there on March 16. Having grown in the coldframe, they are already acclimated to the outdoor temperature fluctuations. Sometimes hairy vetch can be a nuisance in the garden. In the past I’ve used it as a companion to the wheat and rye and you can see that in my cover crop video. You can also see how it became a problem in the rye.
It is good to plant a small amount of a legume into your grain crops and the legume I use now is Austrian winter peas, a winter hardy variety of field peas. Both the vetch and winter peas will grow quite tall and could pull down the grain if left to grow. That doesn’t matter if I’m just cutting the crop to lie down as mulch, but if I want the grain later in the season I need to pull out the vetch or winter peas. Austrian winter peas are much easier to pull out than the vetch. If you are growing grain on a larger scale than your garden bed, you might choose red clover as the companion to the wheat or rye. You can seed it into the growing grain in the spring. The red clover will grow some and provide a nice green cover when the grain is harvested, then it will keep on growing and a harvest can be taken the first summer. Let it grow over the winter, then harvest twice the second summer. After that it is time for another crop for that space.
You can find the best cover crops for your location and situation by reading Managing Cover Crops Profitably, 3rd edition, available from www.sare.org. Be sure to read all the text, not just look at the charts. There is a lot to learn and every time you think you have it down, something else comes along to figure out. The important thing is to let the soil and the garden guide you.
Seems like a lot of work cutting the rye, composting, etc. We just roll down the rye in our field with a roller with tines on it. This crimps the rye stalks adn kills the stalk. Rodale designed a nice roller but it was nearly $5000, so we just added angle iron to a standard yard roller to perfrom the crimping. The crimped rye dies off and provides a mulch layer to suppress weeds and hold moisture. The roots die and help the soil. If I roll it down with the seed heads about half brown, I get the rye to dye off but still get some viable seed that will come up in the fall when I over seed again. There is also a good video at gaininggroundvirginia.org We plant our tomatoes, peppers, squash right into the mulch layer. In our area, Zone 6, I’m looking to roll it down next week.
Steven, I’m glad you’ve had success with that! In 2006 I attended the train-the-trainer workshops/field days Virginia Tech had for cooperative extension and soil and water personnel. I was neither, but invited anyway. I learned just what you’re talking about and got really excited because I realized I could translate that to information people could use in their gardens. These gardens have intensive beds that are never walked on. They generally have a tight rotation and rye reseeding itself would be a nuisance. At the field days I saw examples of the cover crop not always wanting to stay crimped. Cutting it, and on the scale I’m teaching to it’s not a problem, makes sure it stays down. Yes, on a larger scale, different methods and equipment are needed, but the understanding of the system is the same.
Yes, I found I have to make several passes over the field to get a good total crimp on the rye. Agree for small plots, raised beds, cutting may be the way to go. Check out the http://www.gaininggroundvirginia.org video. It made me very hopeful that some of the larger farmers have found success by abandoning tillage. Less fuel use and much better for the soil. I thought the runoff demo in that video was brilliant. Just recently discovered your blog via Farming magazine. Thanks for all the info you share.
Steven, I took a look at the video at http://www.gaininggroundvirginia.org and that runoff demo is really impressive. No-till has been talked about for a long time and the methods used to manage the cover crop was to kill it with Roundup and then plant into the killed residue. I’m glad to see, as you are, an alternative for the large farms to use the roller/crimpers for management. It does require a lot of relearning how to do things, and with those farmers often barely making a profit it is hard to make changes, but the benefits are tremendous. Thanks for mentioning Farming magazine. I was interviewed for that article last summer and didn’t know it had been published.
Enjoyed and learned from the post as usual. I cut down most of my rye several days ago. It went into the compost pile. Also cut the crimson clover but it will stay on the beds it came from. I’m waiting for the vetch to blossom and then it will come out, too. I had great stands of vetch. The rye was only so-so. The oats that I pulled much earlier were better. All these cover crops were on my brand new garden: 16- 100sf beds. I imported screened topsoil since this garden went into a previously wooded area (took the trees down, then added the topsoil, raked into beds) and the remaining roots were a tremendous problem. The topsoil crusted over and became like cement. This spring I’m adding lots of leaf mulch to amend the soil and my husband is tilling. Do hope to not till again. I will manure this fall and continue cover cropping. Any advice for amending the soil? Enjoying spring, Laurel in Spotsy
Laurel, it sounds like you’re on the right track. Building organic matter in your soil is the solution to so many problems. The roots of those cover crops you had growing worked on your garden all winter for you. You might want to have your soil tested so you can identify any deficiencies. Countryside Organice in Waynesboro, http://www.countrysideorganics.com, (formerly Countryside Natural Products in Fishersville) could help you with what organic ammendments you need.
Hi cindy
nice article as expected from the master gardener.Did you attent the visit of John Jeavons at NYC can you write a post if you fell like
I did not attend the workshop in NYC. For those looking for him on the East Coast, John Jeavons will be in Elon, NC for a 2-Day workshop in August. You can find more information, including what topics are covered, at http://www.johnjeavons.info.
how do i manage the pathway ,should i put the cover crops there too and cut them down ? I wage a war against weeds every year! from open plot next to the garden
thanks
In the cover crop video I talked about using white clover in the paths. You can cut it with a sickle when it gets too tall. Of course, you can put a thick layer of leaves down on the paths in the fall when you are raking them up. That should take care of it.
I just had to let you know about my first experience with wheat/vetch/fava beans compost mix from bountiful gardens. I planted the package last year with the intent to cut and lay for my tomato plants. With this weather acting all crazy, the fava beans did not winter kill and the vetch went nuts. Needless to say, after letting the bees have some time, I cut the vetch and pulled the beans (the wheat failed). I could not believe all that bio-mass! It was huge!!! I am sure that my neighbors thought that I had gone nuts. I was hooping and hollering with pure joy. 🙂 I left it lying on the ground and waited and waited until I felt it was safe to put out my tomato plants. I bought several heirloom and hybrid varieties (I haven’t had much luck in the past with either). When I went back to my bed, I pushed aside the mulch and using my fork, loosened the top surface. OMG, the WORMS! There were worms everywhere!!! (I counted ten-15 in one square foot). Again, my neighbors thought I was nuts with all my laughing and and calling out to my kids, “Look kids, worms. Look at all these worms. . .” I was able to use just my hands to dig a hole for each plant. It’s been three weeks now and they are in fantastic shape. I had blooms on the plants within three days of planting and they are a deep green color and STRONG stemmed plants. I have early, mid, and late blooming plants. I wasn’t sure if I was going to use compost crops but now I am convinced. My other bed had crimson clover. My husband cut it down and left it on the ground. It did not do much for weed control (btw, there were zero weeds under the thick vetch mulch) but did help the soil. I found about 5 worms per square feet. I have cucumbers planted and for the first time, I have healthy, green plants. We’ve been working for years on building up the soil with amendments, but I have to say,we’re seeing better results with the cover/compost crops. I am so excited. Thank you, thank you, thank you!!!
THANK YOU for writing! It shows the readers that it’s not just me. I’m glad you can see the results so clearly. As you know, it’s amazing what cover/compost crops can do.
i planted red clover. do i need to “just” cut it and leave it then plant when warm enough? should i use round up then till when time to plant? any info is appreciated
Red clover (different than crimson clover) grows for two years. I only use it when I can let it grow a whole year in a bed, cutting it for compost material and letting it grow back until the next year. Under no circumstances would I recommend the use of chemicals in the garden. You could till red clover in the spring, but I don’t advocate the use of tillers in a garden that can be managed without one. You can read more about red clover in the cover crop book available online http://www.sare.org.