Stevia (Stevia rebaudiana)
3 sources cited · Verified
The short answer
- Plant out
- Late April to mid May
- Site
- 2+ hours of sun, soil pH 5.5–7
- Biggest risk
- Septoria leaf spot of stevia
In the UK, stevia planted out late April to mid May.
Stevia (Stevia rebaudiana) — Tender perennial usually grown as a half-hardy annual outside USDA zones 10-11 (RHS.
Timing is the decision that matters most in Canada: there are 6 separate regional planting out windows, ranging from mid March in Pacific Coastal Mild to early June in Far North & Alpine.
Core growing advice on this page is checked against named horticultural sources — see References.
Regional Planting Calendar
| Region | Plant out |
|---|---|
| Central Continental derived | late April to mid May |
| Prairies & Short-Season Continental derived | late May to early June |
| Pacific Coastal Mild derived | mid March to early April |
| Far North & Alpine derived | early June to mid June |
| Atlantic Maritime derived | early May to late May |
| Inland Valleys & Southern Lakes derived | late April to mid May |
Rows marked derived are interpolated between regions our sources do state, because no source we consulted gives a figure for that region specifically. They are deliberately wider to reflect that uncertainty.
Central Continental - detail & sources
DERIVED from this region's own frost normal, not quoted for the region. Frost-tender; plant outside after all risk of frost has passed (RHS); grown as a tender annual across Canada. Applied to a mean last frost of 30 April (NOAA NCEI 1991-2020 for the USA; Environment and Climate Change Canada normals for Canada), that gives 30 April to 14 May. Your own local frost date is what matters — a region spans a range, and this figure comes from one representative station within it.
Prairies & Short-Season Continental - detail & sources
DERIVED from this region's own frost normal, not quoted for the region. Frost-tender; plant outside after all risk of frost has passed (RHS); grown as a tender annual across Canada. Applied to a mean last frost of 21 May (NOAA NCEI 1991-2020 for the USA; Environment and Climate Change Canada normals for Canada), that gives 21 May to 4 June. Your own local frost date is what matters — a region spans a range, and this figure comes from one representative station within it.
Pacific Coastal Mild - detail & sources
DERIVED from this region's own frost normal, not quoted for the region. Frost-tender; plant outside after all risk of frost has passed (RHS); grown as a tender annual across Canada. Applied to a mean last frost of 18 March (NOAA NCEI 1991-2020 for the USA; Environment and Climate Change Canada normals for Canada), that gives 18 March to 1 April. Your own local frost date is what matters — a region spans a range, and this figure comes from one representative station within it.
Far North & Alpine - detail & sources
DERIVED from this region's own frost normal, not quoted for the region. Frost-tender; plant outside after all risk of frost has passed (RHS); grown as a tender annual across Canada. Applied to a mean last frost of 5 June (NOAA NCEI 1991-2020 for the USA; Environment and Climate Change Canada normals for Canada), that gives 5 June to 19 June. Your own local frost date is what matters — a region spans a range, and this figure comes from one representative station within it.
Atlantic Maritime - detail & sources
DERIVED from this region's own frost normal, not quoted for the region. Frost-tender; plant outside after all risk of frost has passed (RHS); grown as a tender annual across Canada. Applied to a mean last frost of 7 May (NOAA NCEI 1991-2020 for the USA; Environment and Climate Change Canada normals for Canada), that gives 7 May to 21 May. Your own local frost date is what matters — a region spans a range, and this figure comes from one representative station within it.
Inland Valleys & Southern Lakes - detail & sources
DERIVED from this region's own frost normal, not quoted for the region. Frost-tender; plant outside after all risk of frost has passed (RHS); grown as a tender annual across Canada. Applied to a mean last frost of 30 April (NOAA NCEI 1991-2020 for the USA; Environment and Climate Change Canada normals for Canada), that gives 30 April to 14 May. Your own local frost date is what matters — a region spans a range, and this figure comes from one representative station within it.
Quick Facts
At a Glance
Soil & Growing Conditions
Growth Stages
Harvest & Storage
Diseases
Pests
Stevia Photo Gallery
References
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USDA hardiness zones 10a-11b. Full sun (6+ hrs) or partial shade (2-6 hrs). Soil pH acidic (<6.0) to neutral (6.0-8.0), loamy or sandy, well-drained. Spacing 12in-3ft. Height/spread 1-2ft. Propagate by stem cuttings or seed. Leaves harvested approx 90 days after planting; best harvested just as it begins to flower; prune flower buds to improve leaf flavour. Keep soil moist -- overwatering causes root rot. Fertilize every 4-6 weeks during growing season. Blooms July-August, small white tubular flowers in clusters. Pest issues: aphids and spider mites. No known serious disease issues (see separate NC State Septoria leaf spot publication, which documents a real disease not mentioned on this general toolbox page). Native to Brazil and Paraguay. In North Carolina grown as an annual, moved indoors before first frost if kept as a perennial.
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Caused by the fungus Septoria steviae -- stevia is the only known host. Symptoms begin as small necrotic lesions at the base of the plant that move upward in the canopy under favourable conditions; lesions coalesce causing leaf necrosis and eventual defoliation. Pycnidia form within lesions, releasing conidia spread by rain splash. Disease spreads most rapidly in periods of high rainfall with cool night temperatures (typically September-October in North Carolina). When stevia is grown as a perennial, inoculum overwinters in plant debris and re-infects new stems the following season.
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Half-hardy tender perennial often grown as an annual. Propagate by seed; plant outside after all risk of frost has passed. Soil: loam or sand, acid/alkaline/neutral, moist but well-drained. Sun: full sun or partial shade, warm sunny position. Hardiness H3 (-5 to 1C min, coastal/mild UK only). Height/spread 0.5-1m. Leaves harvested for use as a natural sweetener; time to maturity 1-2 years. May be susceptible to thrips and a virus disease. Family Asteraceae. Not native to GB/Ireland.
3 independent sources are cited for this crop. Where they disagree - soil pH is the clearest case - every figure is preserved rather than averaged into false precision.
Frequently Asked Questions
When should I plant stevia out in Canada?
In Pacific Coastal Mild, from mid March. In Far North & Alpine, wait until early June. Treat these as a guide rather than a fixed date — the governing rule is to plant out only once frost risk has passed and temperatures are reliably warm enough.
What soil pH do stevia need?
A pH of about 5.5–7. That span reflects genuine variation between the authorities we cite rather than a single agreed figure — the References section lists each source's exact range.
What problems affect stevia?
Our data links 1 disease and 3 pests to this crop. See the sections above for each one and how to manage it.
Plan next season before the problems start
Short-season growing is arithmetic before it is technique: days to maturity against frost-free days decides what will finish at all. The Canada Garden Planner does that subtraction for your region before you sow.
Get the Canada Garden Planner →Instant PDF download · Written for Canadian growing conditions
Vegetable Growing Guides Canada
Last verified 2026-09-03
Where To Go From Here
Take this crop from reading into a written plan for your own beds.
Plan the next step
Use the printable SoilCommander planner for your region to turn this guide into sowing dates, bed layouts and weekly garden tasks.