Planting Komatsuna
Komatsuna is a cool season vegetable in the Brassicaceae family. Getting the timing right is the difference between a strong stand and a disappointing one, so the windows below are given relative to your own last spring frost and first fall frost rather than a generic calendar date. Look up your local frost dates and count back or forward from there.
You can sow Komatsuna directly into the garden 2–4 weeks before your last frost.
For a fall crop, sow 6–8 weeks before your first fall frost so plants mature as the weather cools.
Spacing and Planting Depth
Give Komatsuna room to mature. The figures below come from verified extension and seed-supplier data for typical varieties.
| Spacing in row | 6 inches |
|---|---|
| Row spacing | 12 inches |
| Plants per sq ft | 2 |
| Planting depth | 0.25 inches |
| Sun requirement | Partial sun |
Plan a square-foot bed with Komatsuna →
Calculate plants in a bed for Komatsuna →
Days to Maturity
Komatsuna reaches maturity in 35–50 days from sowing.
For a continuous harvest, sow a new batch every 14 days. Use the succession planting scheduler →
Komatsuna is ready to harvest after about 43 days. Harvest before summer heat or, for fall crops, before a hard freeze, to keep quality high.
Conditions and Care
As a cool-season vegetable, Komatsuna does its best growing in the cooler weather of spring and fall and tends to bolt or turn bitter in summer heat. It is frost hardy and can shrug off light freezes, so it can stay in the ground later into the season than tender crops.
Komatsuna grows well in partial sun and tolerates some afternoon shade, which can help slow bolting in warm weather. Sow seed about 0.25 inches deep — small seed is sown shallow and barely covered, then keep the soil evenly moist until seedlings establish.
Komatsuna belongs to the Brassicaceae family; rotating where you grow members of this family each year helps limit the build-up of soil-borne pests and disease. Because it matures relatively quickly, Komatsuna rewards succession sowing: small, repeated plantings keep a steady supply coming rather than one short glut.
See Komatsuna in the full planting calendar for your ZIP →
Plan crop rotation for Brassicaceae →
Companion Plants
Pairing Komatsuna with the right neighbors can improve growth and deter pests; a few combinations are best avoided.
Grows well with: Lettuce (Loose-leaf), Spinach
Check Komatsuna with other crops in your garden →
Growing Notes
Japanese mustard spinach.
Related Crops
Other crops you might grow alongside or instead of Komatsuna.
In the same family
Komatsuna is in the Brassicaceae family. Other Brassicaceae crops in the Gardenable database:
Documented companions
These crops are listed as good growing partners for Komatsuna:
Similar growing requirements
Crops with similar season and time to maturity — useful if you want a diverse garden on a similar schedule: