This guide answers when to plant stevia zone 7 with timing worked out from USDA Zone 7 frost-date averages, not guesswork. Stevia is the sweet-leaf plant: its leaves are many times sweeter than sugar, with no calories, and home growers dry and crumble them into teas, baking and homemade sweetener. It is a tender perennial from South America, so in Zone 7 it is grown as a warm-season annual, started indoors and planted out after the last frost.
This guide covers when to plant stevia zone 7, how to start it from seed, what soil and spacing it needs, and how to harvest the leaves at their sweetest.
Zone 7 at a glance
Zone 7 covers areas where average annual minimum temperatures run 0 to 10°F. The average last spring frost falls in the Mar 15–Apr 1 range and the average first autumn frost in the Nov 1–15 range — these are USDA zone averages, not exact dates for any one garden, so check your local extension service before planting tender crops outside. Use the frost date calculator to work out dates for your own garden, and browse the planting calendar hub for the full Zone 7 year.
When to plant stevia in Zone 7
| Step | Timing in Zone 7 |
|---|---|
| Start indoors | February to March, 8 to 10 weeks before the last frost |
| Transplant outdoors | Early to mid-April, after the last frost |
| Direct sow outdoors | Not recommended — seed is slow and unreliable outdoors |
| Pinch tips | May to June, to encourage bushy growth |
| Harvest | July to September, before plants flower |
The table above is the short answer. Stevia is tender and hates cold, so wait until frost danger has passed. Start seed indoors in February to March, 8 to 10 weeks before the average last frost range of Mar 15–Apr 1, and transplant in early to mid-April, once nights are reliably mild. If a late cold snap is forecast after transplanting, cover plants overnight. The season ends with the first frost in the Nov 1–15 range, so harvest the last leaves before then — or lift a plant into a pot and keep it indoors over winter. The Zone 7 April guide shows what else is happening in the garden in that month.
How to plant stevia
Sow indoors in February to March on the surface of seed compost — the tiny seed needs light to germinate, so press it in without covering it, and keep it warm and moist. Germination takes 7–14 days but can be patchy, so sow more seed than you need. Grow seedlings on in bright light and harden them off for a week before transplanting in early to mid-April. Space plants 18–24 inches apart, and pinch out the growing tips when plants are a few inches tall to make them branch.
Give stevia full sun — at least six hours of direct sun a day for full-sun crops, or morning sun with afternoon shade where part shade is listed. Prepare the bed by forking in compost and removing stones and weeds, and check the soil pH: stevia prefers 6.0–7.0. Space plants 18–24 inches apart — the spacing in the table below — and sow seed at the depth on the packet, keeping the seedbed moist until germination, which takes 7–14 days.
| Fact | Range |
|---|---|
| Sun | full sun |
| Days to germination | 7–14 |
| Days to maturity | 90–120 |
| Spacing | 18–24 inches |
| Soil pH | 6.0–7.0 |
| Sowing method | start indoors |
| Cold tolerance | tender |
| Water needs | moderate |
Watering and feeding
Stevia has moderate water needs: keep the soil evenly moist, especially while plants are young and in hot weather, and water at the base in the morning. It wilts quickly in dry soil, so check pots daily in summer. It needs little extra feeding if the soil was enriched with compost — a light liquid feed once a month during growth is enough. Avoid waterlogging, which can rot the roots.
Companion plants and rotation
Good companions for stevia include tomatoes, peppers, marigolds, cabbage. It fits well in a herb bed or at the edge of a vegetable bed, where it gets full sun without shading its neighbours. Rotate annual crops each year rather than planting the same family in the same spot. Also see our guide to when to plant basil in Zone 7, another tender herb started indoors for a Zone 7 summer.
Use the herb drying calculator to plan combinations for your whole bed.
Pests and problems
The common pests for stevia are aphids, slugs, thrips. It has few problems in Zone 7: aphids may cluster on young tips and can be washed off with water, and slugs may nibble young plants in a wet spring. Good air flow helps — do not crowd plants — and watering at the base rather than over the leaves keeps foliage dry. Whiteflies can appear on plants kept indoors, so check leaves before bringing a plant inside for winter. Check plants weekly, looking under leaves as well as on top, and clear away dead leaves and debris where pests hide.
Harvesting and storing
Pick leaves from July to September, about 90–120 days after sowing, cutting whole stems in the morning before the plants flower — the leaves are sweetest just before flowering. Strip the leaves from the stems and dry them in a single layer in a shady, airy place, then crumble and store in a sealed jar away from light. Dried leaves keep for months. Use them whole in tea, or grind them to a powder for baking. If plants start to flower, pinch the buds off to keep the leaves sweet for longer.
Frequently asked questions
When should I plant stevia in Zone 7?
Start indoors in February to March and transplant in early to mid-April, after the average last frost range of Mar 15–Apr 1. These are zone averages, so check your local extension service for your area.
Is stevia perennial in Zone 7?
No — it is tender and will be killed by the first frost in the Nov 1–15 range. Grow it as an annual, or lift a plant into a pot and keep it in a bright, frost-free room over winter.
How long does stevia take to grow?
About 90–120 days to maturity from sowing or transplanting, depending on variety and weather. Germination takes 7–14 days. Warm, sunny weather speeds growth; cold or cloudy weather slows it, so treat these as ranges, not exact dates.
What soil pH does stevia need?
A pH of 6.0–7.0 is ideal. Test your soil before planting and amend it if needed — your local extension service can test a sample and advise on what to add.