Planting Hyssop
Hyssop is a warm season herb in the Lamiaceae 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.
Hyssop is started indoors 8–10 weeks before your last spring frost date, giving seedlings a head start before they move outside.
Transplant young plants outdoors 0–2 weeks after your last frost, once the danger of frost has passed.
Hyssop can be grown by starting indoors and transplanting. Starting indoors gives the longest, most controlled season, while direct sowing is simplest where the season is long enough.
Spacing and Planting Depth
Give Hyssop 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 | 0.125 inches |
| Sun requirement | Full sun |
Days to Maturity
Hyssop reaches maturity in 75–90 days from transplant.
Hyssop is ready to harvest after about 83 days. Harvest before the first fall frost, which will end the plant's productive season.
Conditions and Care
As a warm-season herb, Hyssop needs warm soil and settled weather to thrive, and is set back or killed by frost. It is frost hardy and can shrug off light freezes, so it can stay in the ground later into the season than tender crops.
Hyssop needs full sun — give it at least six hours of direct light a day for the best growth and flavor. Sow seed about 0.125 inches deep — small seed is sown shallow and barely covered, then keep the soil evenly moist until seedlings establish.
Hyssop belongs to the Lamiaceae family; rotating where you grow members of this family each year helps limit the build-up of soil-borne pests and disease. Hyssop is generally grown as a single planting each season rather than succession sown.
Companion Plants
Pairing Hyssop with the right neighbors can improve growth and deter pests; a few combinations are best avoided.
Grows well with: Cabbage, Grape
Keep away from: Radish
Growing Notes
Perennial; traditional companion near brassicas and grapes.