Planting Wasabi
Wasabi 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.
Transplant young plants outdoors 0–2 weeks before your last frost — Wasabi tolerates cool conditions and benefits from an early start.
Spacing and Planting Depth
Give Wasabi room to mature. The figures below come from verified extension and seed-supplier data for typical varieties.
| Spacing in row | 12 inches |
|---|---|
| Row spacing | 18 inches |
| Plants per sq ft | 0.67 |
| Planting depth | 0.5 inches |
| Sun requirement | Shade |
Days to Maturity
Wasabi reaches maturity in 540–730 days from sowing.
Wasabi is ready to harvest after about 635 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, Wasabi does its best growing in the cooler weather of spring and fall and tends to bolt or turn bitter in summer heat. It is half-hardy — it withstands light frost but should be protected from a hard freeze.
Wasabi is one of the few edibles that performs in shade, making it useful for spots that get little direct light. Sow seed about 0.5 inches deep, then keep the soil evenly moist until seedlings establish.
Wasabi 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. Wasabi is generally grown as a single planting each season rather than succession sown.
Growing Notes
Demanding perennial; needs cool running water and deep shade.