Edamame is a wonderful, healthy, and crunchy snack that many people don’t know can be grown in your garden. I wanted to try growing some in the limited space of my container garden.
You can grow edamame in a pot that is at least 12 inches deep and wide. You can grow edamame in the pot because it grows 1 to 3 feet tall. Provide it good potting soil, moisture, nutrients, and 8 hours of direct sunlight so it grows well.
I’ve written all the details you need to know how to grow some edamame in a pot in your own garden. So keep reading.
1. Pick the best time to grow edamame
Edamame is a warm-season plant so the best time to start growing it is in spring when the temperature is at least 65 degrees Fahrenheit. If it’s too cold, the seeds won’t germinate, or the growth will be prolonged.
I would suggest to wait a couple of weeks after the last frost date in your area and only then plant the seeds in the pot.
If you live in a place with a long growing season, you can germinate the seeds in the pot outdoors and continue growing the edamame plant. But if you have a short growing season, you may have to start seeds indoors three weeks before the last frost date. Then you can transplant them outdoors once the weather has warmed up.
Make sure to use a heating mat or place the seed starting trays on top of a refrigerator or an oven so they get plenty of warmth to germinate.
2. Figure out how long edamame takes to grow
Edamame is the fresh, young pod of the soybean plant. So you can harvest them about 45 to 60 days after you have planted seeds. If you allow the pods to dry out after about 100 days, you’ll get soybeans instead.
It’s best to check the seed packets or the label on the seedlings to know the exact dates when the pods will be ready for harvest. The pods will be about 2-4 inches long and bright green in color.
3. Choose the right pot to grow edamame
The good thing about edamame plants is you can grow them in a pot that is 8-12 inches deep and wide. In a large pot, you may be able to grow several plants as long as you keep 6 inches between the plants.
I like to use a plastic pot to grow edamame because it’s inexpensive, durable, and lightweight. You can choose from other materials as well such as terracotta, ceramic, metal, wood, or concrete.
You should make sure the pot has drainage holes at the bottom. This helps it drain out the excess water and protect the roots from getting root rot. If there are no holes, you can drill some before using the pot.
4. Prepare the pot for planting edamame
I like to reuse pots to grow my plants but you may have to buy a new one if you’re starting your garden. In any case, it’s best to sterilize the pot before you can plant edamame.
The easiest way to do this is to prepare a large container with 1 part bleach and 9 parts water. Then soak the pot in this solution for an hour. Remove the pot and rinse it well with water. Then dry it out in the sun before you can use it for planting.
I would recommend using good potting soil rather than garden soil in your pot. The garden soil may have too much sand or clay that is not the right texture for growing bitter melons. The garden soil may contain pests, diseases, and chemicals that can harm the plant.
It’s best to buy potting soil from a garden center that you know provides some with good quality. You can also make your own potting soil by mixing 1 part vermiculite, 1 part perlite, and 1 part coco coir.
If you can make some compost, it’s a good option to add it to the potting soil. This will add nutrients and beneficial organisms to the potting soil.
Fill the pot with the potting soil till there’s a space of 2 inches left from the rim. This will prevent the soil from spilling out when watering.
5. Plant the edamame seeds in the pot
I like to start edamame from seeds because it’s inexpensive, you can grow a lot of them, and you have more options with the variety of seeds to choose from.
It’s also beneficial to start seeds if you have a short growing season. You can start the seeds indoors even if the outside weather is not yet suitable for growing. Once the seedlings have sprouted and the weather has improved, you can transplant them outdoors.
If you have a regular growing season, it’s best to directly sow the seeds into the pot. This helps the seeds germinate and develop strong roots without getting disturbed or facing the stress of transplant.
Edamame seeds need the temperature to be at least 65 degrees Fahrenheit to germinate well. You need to plant the seeds 1-inch deep into the potting soil.
Keep the potting soil moist till the seedlings can germinate. You don’t want to make the soil soggy with too much water as this will cause rotting of the seeds. The seedlings should germinate in about 7-10 days.
6. Plant edamame seedlings in the pot
If you’re a bit lazy and don’t want to start seeds, you can consider buying the seedlings if a nursery or garden center has them. The drawback of buying seedlings is you may be limited in the variety you can grow.
The seedlings will come in a small pot that you need to take the plant out of and transplant to the larger pot outdoors. You must harden the seedlings before you do this.
Hardening is a process where you help the seedlings get used to the outdoor conditions so they don’t get stressed when you transplant them. You do this by keeping the seedlings outdoors for a few hours every day.
You can keep doing this for about a week and the seedlings will have hardened and ready for the transplant outdoors.
Push the seedling out of the container so that the root ball comes out. Then make a hole in the potting soil and place the root ball in it. Cover the root ball with more potting soil and press near the base so it becomes stable.
Now you should water the potting soil well so it can settle and the roots can get comfortable in the new pot.
7. Place the pot in the right location for sunlight
Edamame is a warm-season plant that needs full sun to grow well. This means you need to place the pot in a location that gets at least 6-8 hours of direct sunlight every day.
At the same time, you do not want too much heat on the plant as the leaves will wilt and the plant can stop growing. If the temperature gets too high, consider moving the pot in the shade till it returns to normal.
8. Give edamame plants required watering
The edamame plant is going to need a lot of water but you want to avoid overwatering the plant. I suggest checking on the potting soil every morning.
You want the top 1-inch of the potting soil to dry out before you consider watering it again. Stick your finger 1-inch into the potting soil and check for the moisture.
If it feels dry, you can water the potting soil thoroughly till the water drains out from the drainage holes at the bottom of the pot. This ensures that the potting soil as well as the roots have got the required moisture.
The drainage holes will help you prevent the problem of underwatering or overwatering that will stunt the growth of the edamame plant or kill it.
If you are afraid to water the plant, you’ll give it less water and stunt its growth. If you give too much water and it remains in the pot it will lead to overwatering. This will cause root rot or fungal diseases and cause the plant to die.
I would suggest adding mulch to the potting soil after the seedlings have grown 4-6 inches tall. The mulch will help keep the temperature regulated so you don’t have to water the soil as often.
You can use materials like dried leaves, grass clippings, straw, hay, wood chips as mulch. Add 2 inches of such material on the potting soil after the seedlings have germinated and grown 2-4 inches in height.
9. Thin unwanted edamame seedlings
You should always plant 2-3 seeds when planting edamame. This helps increase the chances that at least one of the seeds will germinate.
But there is the possibility that all of the seeds may germinate. You cannot allow all of the plants to grow because they will compete with each other for nutrients. They will also crowd each other increasing the chances of fungal diseases.
Thinning means you keep one of the seedlings and cut off the remaining as you only want to grow one of them. You can move the remaining seedlings to another pot if you wish to grow more plants. Otherwise, you can dispose of them.
You can think about thinning when the seedlings have grown 3-4 inches tall and have developed a few leaves.
10. Fertilize edamame plants in the pot
My number one choice for providing nutrients to the edamame plant is by adding compost to the potting soil. You do this at the start when preparing the pot by mixing in some compost with the potting soil.
And you can continue adding a little compost every month to the potting soil to give the edamame plant a boost of nutrients.
The compost helps provide nutrients and beneficial microorganisms to the potting soil. It also improves the texture.
If you don’t have compost, you can add a slow-release granular fertilizer to the potting soil when preparing it.
The edamame plant is a legume which means it’s capable of fixing nitrogen in the soil by taking the help of nitrogen-fixing bacteria in the soil.
That’s why I suggest only using a fertilizer that is low in nitrogen and rich in potassium and phosphorus such as one having an N-P-K value of 5-10-10.
If you try to use a fertilizer that is high in nitrogen it will cause the plant to focus too much on developing foliage rather than the pods.
You can also use liquid fertilizer instead and spray it in the potting soil every couple of weeks. The liquid fertilizer can be fast-action especially if you spray it on the foliage.
Make sure to follow the manufacturer’s instructions when using any fertilizer. It will give you information on how much fertilizer to use and how often. I would also recommend using an organic fertilizer rather than chemical.
11. Pollinate edamame plants in the pot
The good thing about the flowers of edamame plants is they are self-pollinating. This means that the pollen from the flower fertilizes the ovary in the same flower causing them to develop pods.
So you don’t need to worry about attracting beneficial pollinators to your container garden. And you don’t need to worry about hand-pollinating either.
12. Prune edamame plants in the pot
When you prune the plant, you cut off parts of the plant so it helps it to grow better. This could be cutting off both dead or live parts of the plant.
You can cut the foliage, branches, and even pods of the plant that could be dead, diseased, or even healthy ones.
The purpose of pruning is so the plant can spend more energy on growing flowers and pods rather than on the foliage or dead parts. If you prune the leaves when it’s growing, the plant will grow more leaves. If you prune the plant when it’s developing flowers, it will grow more flowers.
I recommend not cutting off more than 1/3rd of the edamame plant at one time. This will prevent the plant from developing stress that can stunt its growth or kill it.
I suggest using a bypass pruner when doing the pruning. They will help you get a clean cut and reduce the chances of infection. Make sure to clean them before and after use with rubbing alcohol.
13. Harvest edamame from the pot
You know it’s time to harvest the edamame from the plant when the pods are bright green in color and have a height of 2-4 inches. If you leave the pods for a longer time, they will dry out and develop soybeans.
You can check the seed packets that will give you a precise date on when they will be ready for harvest.
To harvest the pods, you can twist and pull them by hand. But I suggest using a bypass pruner as that will minimize the damage to the plant. This prevents the plant from infection by fungal or bacterial diseases near the cut.
You can store the fresh edamame pods for a week in the refrigerator without losing their taste and texture. If you want to store them for a longer period of time, you’ll need to freeze them.
Boil them in water for 3 minutes and immediately put them in a container filled with ice-cold water for the same amount of time. Now put them in a paper towel so the water can be dried out.
Now you can put the edamame pods in a freezer bag and store them in the freezer for up to a year.