I was never a huge fan of edamame soybeans, that is until I started growing them myself and discovered the sweet, delicious flavor and delightful firm texture of the ripening beans fresh from the bush and then quickly steamed or boiled.
And it turns out that edamame soybean plants are among the fastest growing, most productive, and least insect- or disease-prone of all vegetables. They are super tough in drought conditions, in clay soil, and in some shade. Wow.
Okay, so the soybean is a legume and not a true vegetable, but soybean makes a great addition to either a standard vegetable garden or a more nuanced edible landscape. For, you see, not only is the soybean plant healthy looking by itself and compared to other vegetables, but soybean is so inconspicuous and low-growing (about 2 feet high) that it blends right in with showier plants.
If you think there's a chance you can get between 60 and 90 days of growing season still this year, 2012, go for it. Plant a small patch of edamame soybeans and see how they do in that short time. They want warm soil, so why not try a late summer planting around September 1.
More good features
When you plant soybeans, be sure to get the "edamame" type that is more tender and less oily than the livestock feed soybeans. And there are many varieties of the edamame. Not all seed catalogs carry soybeans, but here are a few sources I know about: High Mowing Seeds, Botanical Interests, Seed Savers Exchange, and R.H. Shumway's, plus one I'll describe below.
At various stages of its growth the edamame soybean can be used as green manure (dig the plants under when the buds are forming), as rabbit or poultry feed in a farm setting (stems, bean pods, leaves, and all), or as soybean hay (the plants dried in the sun and baled).
In the diet, the beans can be eaten in the green stage or processed into a textured meat substitute or milk substitute, or made into the soybean curd called tofu. Asian cuisine has used soybeans for thousands of years. Edamame soybeans contain about 40 percent protein, so they're a good bargain nutritionally.
So easy to grow
Last season, in 2011, I grew some edamame soybeans for the first time strictly as research, as I was trying to produce specimens of 50 different vegetable garden favorites for my new book due out in spring 2013 (it will probably be called Vegevore! 50 Great Vegetables from A to Z, and will be published by Gibbs Smith, Publisher). In that case I started with half a packet of Sweet Sansei Soy Bean by New Dimension Seed, which was the soybean available at my local garden center; cost, $2.95.
Round about June 1, once the soil had really started warming up, I sowed half the packet in my tiny garden, for a total of two abbreviated rows of about 4 feet each. The soil was fine, but I had to put them in a spot where the sun didn't shine directly until early afternoon, and then only for a few hours. But about 10 days later up popped the seeds, and when they all got to 2 feet high they set up a bunch of fuzzy green little pods hanging beneath the pretty leaves, each with two or three "beans" apiece.
Alas, I was headed out of town, plus pretty clueless, so I didn't do much with the harvest.
This season, though, 2012, I was working up some new soil in a vacant lot my husband and I have recently bought, and figured, let's try the second half of that soybean packet from last year. This time the spot was sunny all morning; the soil a bit thin looking, though, and there was no water except rainfall available to sustain them.
In went two rows of 3 feet each, about mid-June, spaced 2 inches apart in 1 inch of soil. Up they popped inside of two weeks, grew steadily to 2 feet high, and set bunches and bunches of pods.
Pick, cook, eat or freeze
Once the soybean pods reach about 2 inches in length and plump up, they are ready to pick. Generally the lower part of the plant ripens first, and there is indeed a prolonged harvest period of some weeks. Every evening recently I have gone over to the vacant lot with a sieve and picked a few big handfuls of soybeans about dusk.
Then I come home, rinse them, put them on to boil for 5 or 10 minutes in a little bit of water, and then cool. Soybeans must be steam blasted or boiled for a little bit to break down an enzyme that prevents their easy digestion. Or at least that's what I have read.
Once the beans cool, simply serve them with some dark soy sauce on the side. Pop the beans out of the hulls and eat. The seed packet from New Dimension Seed includes a recipe for boiled green soybeans with shells which includes spices like fennel seed and bay leaf, both easy to grow in the edible landscape. Any way you choose to cook green soybeans, they are wonderful.
Now, to really stretch the harvest, plant a whole lot of soybeans. More than you can really eat in a few weeks. Harvest frequently and steam or boil the pods as before. Then you can freeze the soybeans for winter use, either in the pod or shelled. And to go one step further, vacuum seal the packs before freezing to remove air and increase effective freezer time. I have used an Oliso vacuum sealer and it's pretty cool.
If you're too late for soybeans this season, make sure to order them next winter and be ready to plant starting sometime in June.
Nan K. Chase writes and grows edamame soybeans at her home near downtown Asheville, North Carolina. She is the author of Eat YourYard! Edible trees, shrubs, vines, herbs and flowers for your landscape and co-author, with Chris McCurry, of BarkHouse Style: Sustainable Designs from Nature. She lectures frequently about edible landscape design.