Herb · Asteraceae
When to plant stevia
A tender perennial grown as an annual wherever there is frost. Leaves are sweetest just before it flowers, so pinch out the buds to delay that.
Start seed indoors
8 weeks before
Counted from your last spring frost.
Plant out
2 weeks after
Counted from your last spring frost.
First worthwhile crop
Year 1
After planting, not after sowing.
Those weeks become real dates once you name a place.
Timing, in frost-relative terms
Seed packets rarely give calendar dates, because a date that suits one latitude is wrong at another. They give offsets from the last spring frost instead, and those offsets are what make stevia plantable anywhere.
- Start seed indoors 8 weeks before the last frost.
- Plant out 2 weeks after the last frost.
- Expect a first worthwhile crop in year 1 after planting.
- Hardy in USDA zones 9a–11a.
Getting the timing right
Start indoors 8 weeks before the last frost and plant out well after it - stevia sulks in cold soil. Cuttings are more reliable than the seed, which germinates erratically.
Frost tolerance
Killed at 0C. Overwinters only where frost-free, or as a container plant brought inside.
Classified as tender, with damage expected below 0°C (32°F)32°F (0°C).