Growing komatsuna is relatively easy, because the plants grow very fast and become mature within just 40 days. The plants are very hardy, drought tolerant and can actually be sown and grown year round in many climates. Japan and Taiwan are growing komatsuna commercially.
The komatsuna is a leaf vegetable and a variety of Brassica rapa. It is also known as Japanese mustard spinach. The name ‘komatsuna’ is from the Japanese komatsuna, ‘greens of Komatsu’, a reference to Komatsugawa village where it was heavily grown during the Edo period.
Komatsuna is very nutritious and rich in vitamins and minerals (an excellent source of calcium). It is stir-fried, pickled, boiled and added to sups or used fresh in salads. The leaves can be eaten at any stage of their growth. Leaves of the mature plant are dark green with slender light green stalks (around 12 inches long and 7 inches wide).
How to Grow Komatsuna
Growing komatsuna in home garden is not too difficult. It is a biennial plant that is tolerant of very cold temperatures as well as the heat (but extreme heat may cause it to bolt). However here we are describing more information about growing komatsuna in your home garden.
Select a Location
Select a good location inside your garden for growing komatsuna. The komatsuna plants grow well in sunny area and in well-drained soil.
Prepare the Soil
Nitrogen rich soil is considered good for growing komatsuna. So before planting, prepare the soil by adding as much organic materials as you can. Till the soil and add well-rotted manure or decomposed compost.
The komatsuna plants are grown from seeds. So, purchase good quality seeds from any of your nearest market or garden centers.
Best Time for Growing Komatsuna
The komatsuna plants can be grown throughout the year. But they are most often grown in the spring and autumn, because the plants cannot endure extreme heat or cold for more than a short time.
You can either sow the seeds directly in the garden or start the seeds early indoors. You can plant the seeds in rows, which should be 12-18 inches apart. Sow the seeds to 4-6 inches apart, and thin later to about 12 inches apart when the seedlings are 4-6 inches tall. You can use the thinnings in salads.
Taking additional care will help the plants to grow better. The komatsuna plants generally require high amount of nitrogen. So you will need to amend the soil with compost and use a nitrogen rich fertilizer as the plants mature (blood meal is a very good source of nitrogen).
You don’t have to water the komatsuna plants too often. Because the plants are drought tolerant. But consistent irrigation will help the plants to grow well. Try to keep the area free from weeds either by hoeing or by hand. Use mulch in the garden for retaining moisture into the soil and also for controlling most of the weeds.
The good thing about growing komatsuna is that ‘you can actually harvest the leaves at any stage, and can be snipped one at a time or the entire head can be taken. Harvesting leaves will be good. Because the plants will regrow and extend the length of time you can harvest, if you harvest the leaves only. Plant small areas in succession, for a continuous supply year round. Good luck!