Buckwheat as a green manure?

Last fall I cleared out a large section of my oldest bed. I was going to work in alfalfa pellets this Spring, but then started reading about the benefits of growing buckwheat and working it in to provide more available phosphorus in the soil.

If anyone has done this, I'd love to know your results.

Thanks,
Neil

Soil improvement
Buckwheat produces about 1.5 tons/acre dry matter and
takes up about 18 lb of nitrogen (N) per ton of dry matter
(NRCS). Buckwheat has a tissue content of about
1.2% N. Buckwheat is often called a phosphorus (P)
“scavenger” because it can take up soil P more efficiently
than other plants. In its growing stage, the roots of buckwheat
exude substances that help to solubilize P that
may otherwise be unavailable to plants. The roots of
buckwheat were also found to have a high storage capacity
for inorganic P. As a result, when buckwheat
plants are incorporated in the soil, they decay quickly,
making phosphorus and other nutrients available to the
succeeding crop.

I haven't tried it but some friends did. You have to put it in and let it grow and turn it under before it makes seeds or it becomes a weed. But I think it is very good for your soil.

Picture updates.... This is just before I've turned the buckwheat back into the soil. It releases a chemical that keeps weeds from sprouting. I learned that phosphorus in the soil that other plants can't absorb is extracted from the soil and stored in the roots, stalks, and leaves during the first forty days of growth, up to the onset of flowering. As the plants decay other plants can now absorb the phosphorus. The test will be how the iris replanted in this bed perform next year.

One more:

I will be very interested in hearing how the irises planted in the plowed under buckwheat do -- if that works better than alfalfa pellets and bone meal. I know that in general growing buckwheat is a very good idea.

Hi Neil - I'm a BIG fan of buckwheat and use it extensively in the beds here; I buy three fifty pound sacks a year. I let some of it go to seed in the beds, and it shows up the following year, so this has become a nice cycle which suppresses weeds and gets nutrients into the soil without a lot of effort. I also use alfalfa meal, because that's a legume and will provide different nutrients. Same with bone meal - I use it when I plant for a quick boost to the developing roots, figuring it's worth the cost to have the timing exactly right.

The sprouting buckwheat (I seed it several times a season, including right when I plant) provides very quick shade which prevents other weeds from sprouting, breaks down really quickly when it's surface-tilled, doesn't clog up the tiller then way legume cover crops can if you let them go too long, and hand weeds easily - the root system is negligible. In fact if the stalks are bent, the plant will poop out, so I can use a long handled tool to knock them over between the rhizomes, where a tiller could not reach.

I will hand weed around each newly planted rhizome so that it gets sun and air, but I think the bit of shade that the buckwheat in between rows provides the rhizomes is a benefit in the first few weeks after transplanting. I've noticed that transplanted rhizomes in a buckwheat bed, which will get some protection from sun, do not get the bleached-out fans that the ones in direct sunlight seem to get, and seem to settle in faster. We're not talking Shade of Death here - just enough for a filter.

In theory - never works out perfectly of course, due to human error - the buckwheat gets tilled in when it's about ten inches tall. I've been using a rotary gas powered tiller but I'm concerned about soil compaction under the depth of the tines, so I've started shifting the cleaner beds to a rotary push-tiller from Lehman's, and hope to transition them all in the next few years. Unlike the gas tiller, it gets constipated easily, but environmentally it's a comfortable choice. Until I bought two truckloads of compost this spring to amend beds and then discovered it was infested with mile-a-minute weed, vetch, and chicory, the buckwheat was working beautifully to suppress weeds, and I'm sure it will help win the next round.

katie

Great to hear from some one who really knows from experience how to use buckwheat. I need to start using it again.

Thanks, Katie, for all the "hands-on" experience. I do like that there wasn't a single weed in amongst the buckwheat as opposed to the iris beds surrounding the buckwheat. It's too hot and dry here to sow a second crop right now..... but maybe after I replant the bed, I might sow some more around the rhizomes and then hoe it in before it gets too big.

I was also wondering about mixing alfalfa in, also.

Thanks so much for responding.

That was an interesting discussion. Do any of you folks have other tips for
organic feeding of iris? I do not have a setup for composting and I wouldn't
use my town's "compost" made from their yard waste pickup on a bet. It has
probably every plant disease and seed native to the area.

I have read of using alfalfa pellets or meal for the enzymes contained in it but
the buckwheat is new to me. As a novice, I am learning to stay away from
most of the chemical fertilizers.

I don't know about Salem, Ill, but I think the town's composted waste can be a good thing. I don't use mine on veggies but I use it on any ornamental including iris. In our town they compost the yard waste with manure from the horse stable, after grinding up all the branches and large stuff. What I object to in our town's composted waste is the use of the local sewerage sludge. They compost the sludge to high temperatures and the state department of health tests it to be sure it doesn't contain dangerous bacteria ( it gets pretty hot), but sewerage sludge tends to contain heavy metals from the stuff people pour down their drains. No amount of composting will get rid of it.
You might inquire what your town adds to its compost and what testing is done to it. I use the compost from my town for ornamentals, including iris. I just don't use it for veggies.

I only use organic methods, although mine may not all be feasible for everyone. Here's the rundown, sorry it's long:

Before winter, I will put two inches of woodchips in the rows between iris. We're talking four to six inches away from the actual rhizomes, but it will be thickly laid. I do this after it's too cold to grow buckwheat in those rows. This will suppress weeds in the spring before I can start buckwheat again, soaks up extra moisture in my bad-drainage beds, and has the added benefit of proving non-muddy footing for spring weeding after heavy rains. I did not decide to use woodchips because they have any magical properties......I can just get truckloads free from a landscaper friend. The piles sit for a year before I use them, which can be important if the trees had climbing vines that might have seeded; the heat generated as they sit and break down will kill most seeds.

I tried hay flakes this year the same way - they're not mulching the iris, but creating a barrier in the space between rows. Too soon to have an opinion about the effectiveness, but in the damp spring we had, I thought it triggered some of my allergies.

Every three years, each bed is renovated, and the rows shift over by one step - what was a row of iris will now be buckwheat and mulch, what was formerly planted with buckwheat and mulched for winter will be planted with iris. This puts rhizomes into freshened soil every three years at the very least. Some beds are done more often. This is an enormous amount of work, but keep in mind that I'm now self-employed raising iris, and my boss is a witch..........

When a bed is emptied, I scatter the chickenfeed there every morning until I'm ready to replant, and the girls eat breakfast, forage for seeds and bugs, and have a poop. Chicken poop is too hot for immediate use, but this is not a large amount.

We raise rabbits and I am essentially converting large amounts of pulled weeds to bunny poop, which is excellent as an immediate use fertilizer. I've learned that my rebloomers will do better if they get a dose of rabbit poop right about now (darn, one more thing for the list this week.) So when I plant, I'm putting iris into two years' worth of tilled in buckwheat, two years' worth of decomposed wood chips, alfalfa meal (which I add before planting), rabbit poop, and the occasional random chicken poop. I put a small amount of bone meal in with each rhizome because it's the most costly additive I use.

I have experimented with compost tea made from comfrey leaves, alfalfa pellets, and rabbit poops put into an old smelly gym sock which is tied shut and fermented in a five gallon bucket of water for three weeks. That stuff, let me tell you, will revive the most pathetic rescued rhizome, you know, that you've scraped rot off of and killed a borer in, but can't bring yourself to throw out. I mean, you could grow anything with that stuff. But spill it on your jeans and they cannot be worn indoors ever again no matter what you do. Get it on your hands and you will have no social life for a week.

I have experimented with a flame weeder, which uses a small propane torch, for clearing dead leaves over the winter. Had a marvelous time playing with it, but I scorched a couple of markers when I accidentally set larger clumps of brush on fire, and figured I'd stop before I set fire to my shoes or something. In saner hands, it could be effective.

Corn gluten is a surprisingly effective germination-inhibitor and is a main ingredient in a number of commercially available powdered organic weedkillers, and a filler in many chemical ones. A 50 pound sack is only a few dollars at a feed store.

One thing I'll never do again is use Chinese weeder geese. They're beautiful, and the they're incredibly effective. They storm down the rows eating everything that's not an iris. Unfortunately they're also very territorial, and they attacked the UPS man, who is still holding a grudge, and the poop output from those things defies imagination.

The mantra for organic vegetable farmers is "grow the soil, and the soil will grow the food". Iris aren't heavy feeders like my cole crops or corn, but it's still a sensible approach.

katie

Katie,
Your post is very interesting and inspiring. I love the way you give us the low down on all these organic methods. I guess the only one you don't recommend is the Chinese weeder geese. So sorry you learned on the UPS man. I could see why he might be angry. I probably never use the comfrey and rabbit poop tea. No comfrey or rabbit poop available, but the idea sounds great for those who are brave.

Do keep us informed about your methods for growing organic iris. I bet they will work on iris and many other plants. As far as I am concerned to the degree we are able to use organic methods, even on crops we don't eat, like iris, the better off our whole property will be -- also our iris.

Yes, I'm often asked why it would matter to use organic methods for something inedible, but there's two parts to the organic motivation, and only one involves producing residue-free food. The other is the part about treating the earth with more respect in general. I've been involved with farming long enough, though, to know that it's never quite as easy as it sounds, and when your livelihood depends on your product, sometimes you do what you have to do. So no judgment from here on anyone else's choices; I'm just doing what I have to do.

I don't have too much choice, though, because I also grow market vegetables organically, and to sell them that way, I absolutely can't use non-organic methods elsewhere on the property; it's a package deal.

katie