Hot peppers are made for Zone 10: they love heat, they thrive in the long season, and the hotter the weather, the hotter the peppers. From mild jalapeños to fiery habaneros, a few plants will give you more chillies than a household can use — and the plants themselves are attractive, with glossy leaves and bright fruit that look good in a pot on a sunny patio.
In Zone 10, hot peppers can be grown in two seasons, spring and autumn, and like bell peppers they may survive the mild winter as short-lived perennials.
Zone 10 at a glance
USDA Zone 10 covers the warmest parts of the United States, including southern Florida, southern coastal California, Hawaii and Puerto Rico. Winters are very mild, with average winter lows of 30 to 40°F, frost is rare, and the growing season runs nearly all year.
The average last spring frost is Jan 15–30 (frost rare) and the average first autumn frost is Dec 15–31 (frost rare) — USDA/NOAA averages, not exact dates, so check your local extension service before planting.
| Detail | Zone 10 guidance |
|---|---|
| Average winter low | 30 to 40°F |
| Average last spring frost | Jan 15–30 (frost rare) |
| Average first autumn frost | Dec 15–31 (frost rare) |
| Days to germination | 7–14 days |
| Days to maturity | 70–90 days |
| Sowing | start indoors |
| Sun | full sun |
| Soil pH | 6.0–6.8 |
| Spacing | 18–24 inches |
| Water needs | moderate |
| Cold tolerance | tender |
When to plant hot peppers in Zone 10
Plant hot peppers in Zone 10 in two seasons: a spring planting from February through April, and an autumn planting from August through September. Seeds germinate in 7–14 days and fruit matures in 70–90 days, so a February planting is cropping by May, and an August planting fruits from November onwards. The average last spring frost in Zone 10 is Jan 15–30, with frost rare, and the average first autumn frost is Dec 15–31, with frost rare — those are USDA zone averages, not exact dates for any one garden, so always check your local extension service for your own frost dates. Hot peppers are tender and need warm soil, so do not rush the spring planting: wait until nights are reliably mild. Some very hot varieties, like habaneros, take longer to mature than mild ones, so start them earliest.
Work back from the frost dates: the planting calendar hub and the March in Zone 10 month guide show what else is happening at planting time.
Starting hot peppers in Zone 10
Start hot peppers indoors from seed, eight to ten weeks before you plan to plant out — sow in December or January for a spring planting, and in June for an autumn planting. Pepper seed needs warmth to germinate: keep it warm and be patient, since germination takes 7–14 days and can be slower for hot varieties. Grow seedlings in the strongest light you can give them, potting them on once, and harden them off for a week before they go outside. Transplant out only once nights are reliably mild, spacing plants 18–24 inches apart. Put a stake in at planting time — a pepper loaded with fruit will flop over in wind or heavy rain.
See also when to plant hot peppers in Zone 8 for the same crop in a cooler zone.
Soil, spacing, sun and water
Hot peppers need full sun and rich, well-drained soil with a pH of 6.0–6.8. Dig in well-rotted compost before planting — peppers are hungry plants, and a well-fed plant produces far more fruit. Space plants 18–24 inches apart so air can move between them; crowded plants stay damp and invite disease. Water needs are moderate: keep the soil evenly moist, especially while fruit is setting and swelling, because uneven watering causes blossom-end rot. Mulch thickly to hold moisture and keep roots cool, and water at the base in the morning so leaves dry before night. The plant spacing calculator can help you plan the bed before you plant.
Companion planting
Good companions for hot peppers include marigolds, basil, onions and lettuce. Basil and marigolds at the bed edge are said to deter pests, while onions and lettuce fill the gaps between young plants. Do not plant hot peppers right next to bell peppers if you plan to save seed — they can cross-pollinate, and the seed may produce hot offspring — though the fruit of this year's plants will not be affected. Eggplant is another heat-loving Zone 10 crop with the same timing, and our guide to when to plant eggplant in Zone 10 shows how the two can be grown side by side. The companion planting finder can suggest combinations for your whole bed.
Pests and problems
The common pests to watch for with hot peppers are aphids, hornworms, flea beetles and whiteflies. Aphids cluster on soft new growth and buds; wash them off with a strong jet of water and encourage ladybirds. Hornworms are big green caterpillars that strip leaves fast; hand-pick them, checking the undersides of leaves. Flea beetles make small holes in the leaves of young plants; cover seedlings with insect mesh until they are established. Whiteflies flutter up in clouds when disturbed and feed on the undersides of leaves; yellow sticky traps and good air flow help.
Harvest and storage
Hot peppers take 70–90 days to maturity from transplanting, so Zone 10 spring plants set out in February start cropping in May, and autumn plants set out in August fruit from November onwards. Pick peppers when they are full-sized and firm — green, or leave them on the plant to ripen to red, orange or yellow for a fuller flavour and more heat. Cut the fruit with scissors or a knife, leaving a short stem, and wear gloves for the hottest types. Pick little and often: regular picking encourages the plant to set more fruit. Store fresh chillies in the fridge and use within a week, or dry them — string them up in a dry, airy place, or dry them in a low oven — and store in a jar.
Frequently asked questions
When should I plant hot peppers in Zone 10?
Plant in two seasons: spring (February–April) and autumn (August–September). Seeds germinate in 7–14 days and fruit matures in 70–90 days. Start very hot varieties earliest — they take longest to mature.
Why are my hot peppers not hot?
Usually variety, or too much water and fertiliser. Heat varies by variety — a jalapeño will never be as hot as a habanero — and slightly less water once fruit has set is said to increase heat. Do not let plants wilt badly, though.
Can hot peppers cross-pollinate with bell peppers?
Yes, if grown close together — but it only affects the seed, not this year's fruit. Your bell peppers will stay sweet this season; only save seed from peppers grown in isolation if you want true-to-type plants.