If you wish to enjoy the most tasty Edamame beans simply grow some in your greenhouse so you can pick these really fresh. Edamame are green beans, steamed and podded hot or cold they’re gourmet delights very popular in Japanese cuisine. They’re also nutritionally rich in Vitamin C & K, Elements Ca, Fe, Mg, P, folates and Omega 3 fatty acids, as well as protein and fibre, a genuine ‘super-food’.
If left to ripen and dry Edamame become Soya beans, however the dried beans are relatively inexpensive so barely worth cultivating, whereas the fresh are expensive and seldom either fresh and or available. And although Soya beans can theoretically be grown outdoors in the UK their yields have so far proved unsatisfactory.
Under cover though these plants revel in the warmth, grow easily and crop prolifically. And as there are gorgeous yellow foliaged varieties as well as green they can even feature amongst otherwise more ornamental displays.
Soya beans are also remarkable subjects as seldom ever suffering pest or disease and thriving in poor compost, indeed disliking too much fertility. Other than watering their only requirement, depending on variety, is tying to a cane as Edamame can grow up to a metre or so and sheer weight of crop may pull them over if left too long unpicked.
Start the seed off early in the year, these need a long season so the earlier the better. Sow individually in cells or small pots of sowing compost and keep warm and moist. As the seedlings grow pot them on, eventually into tubs or bags of compost, gritty free draining but not rich. You can squeeze three plants in a bucket size tub but for ‘show’ specimens one apiece.
The flowers are small and ephemeral so seldom seen, the small pods appearing and proliferating almost like magic. These furry pods can be picked from as soon as you can discern the swelling of the seeds within the pods, obviously left a little longer these get larger and firmer though left till the pods wither they’ll become tough. If left till the leaves drop the whole plant can be hung up to dry off and the soya beans cooked in winter (after soaking overnight).
If you’re already a connoisseur of Edamame then you have innumerable Asian varieties to find and compare, with the improved Fiskeby V (apparently bred in Sweden) most widely available here.