How to grow Edamame beans

Here’s our ultimate guide to growing your own edamame beans. 

Are you looking for a new high protein addition to the vegetable garden? These sought-after edamame beans make a nutritious and delicious snack or meal accompaniment, and new hardier varieties make growing them outdoors in the UK easier than ever before! Here we explain how to sow, grow and harvest these increasingly popular vegetable seeds.

What is an Edamame bean?

An edamame bean is an immature soybean, picked, cooked and eaten when the beans are still fresh and green. The latin name for the edamame bean is Glycine max, andit belongs to the legume family (Fabaceae) along with other popular beans like French beans, broad beans and runner beans. 

This low calorie food was grown and eaten in China over 2000 years ago. Edamame are still popular in China and Japan, where they are served as a salted side dish, starter or snack. In Japanese, edamame translates to ‘stem beans’ because of the traditional method of selling the beans while still attached to the stem. Edamame are now appreciated around the world for their high nutritional value, especially for boosting the protein content of vegan and vegetarian diets. 

Can I grow edamame beans outdoors in the UK?

Edamame seeds bred to cope with the UK’s cool climate are best sown outdoors. Older varieties traditionally needed a long summer with temperatures between 20 and 30 degrees to grow successfully. Move your edamame plants outdoors when conditions are completely frost free, poor growth is often caused by planting out too early in low temperatures.

Avoid sowing soybean seeds to harvest as edamame. Choose specifically labelled edamame seeds, as they are intended for picking early, producing larger sized beans with a sweeter flavour when immature.

How to sow edamame seeds

Follow these steps to sow your edamame bean seeds between April and mid-June:

• Sow your seeds in pots or trays, under 4cm (1½”) of good quality seed compost.
• Water your trays lightly using a watering can with a fine rosette. 
• Place your seeds on a warm windowsill or in the greenhouse.
• Germination takes 7 to 14 days.
• Pot on your plantlets once they have a few true leaves and they start to look cramped in the module trays. Keep the young plants in a bright sunny position.
• Alternatively, once the soil has warmed up, sow your seeds directly outdoors in a sunny and well drained spot. Cover the sown seeds with frost protection fleece or cloches.

How to grow edamame plants

Grow your edamame beans either in pots on the patio or outdoors in the vegetable patch. Wherever you grow them, keep your plants healthy and happy following the steps below:

• Harden off your young edamame plants for a week or two before moving them outside.
• Plant your edamame, once the danger of frost has passed, in a well-drained yet moist, sunny position about 15cm apart, in rows 45cm apart.
• Consider supporting your beans in high winds. They grow to around a metre tall but are normally self supporting. 
• Keep your plants weed free using a hoe and water them regularly.

When can I harvest my edamame beans?

Harvest your pods when they are bright green, and the individual beans are clearly distinguishable inside. To remove the beans, simply pinch the pod between thumb and forefinger to pop them out. Or, do it Japanese style and cook the entire thing and serve with salt. As soon as you bite into it, the juicy beans will just pop out into your mouth. Remember that edamame beans require a good ten minutes of boiling before they become edible. 

Can I use my edamame seeds to grow soybeans?

You can leave your edamame beans on the plant to ripen into soybeans. At the very end of summer when the plant’s leaves begin to drop, harvest the ripe yellowish pods. Store your soybeans in a dry airtight container. Remember to thoroughly cook your soybeans before eating.

We hope you now feel able to grow your own fresh edamame beans from scratch! Whether you grow your plants in pots or the vegetable patch, tag us in your edamame posts on Instagram or Twitter. We love to see what you do.

Lead image: Bean Soya Seeds – Edamame from Suttons