When to plant kale zone 13 — in USDA Zone 13, that question has a different answer from almost anywhere else in the United States. Zone 13 is the hottest USDA zone, frost-free year-round with average winter lows above 60°F, so there is no last frost to wait for and no first frost to beat. Instead you plant by heat and by the wet and dry seasons, and kale is a cool-season crop, and in Zone 13 it is a coolest-months-only crop. This guide gives the timing and the honest limits, using published crop ranges — and, as always, check your local extension service for varieties suited to your area.
When to plant kale in Zone 13
Kale is the most heat-tolerant of the brassicas, and in Zone 13 it is the best bet of the cool-season leafy greens. It still prefers the coolest months, roughly December through February, but it copes with warmth far better than lettuce or spinach, and with afternoon shade it can keep producing into the warmer months. Grow it as a cut-and-come-again leafy crop rather than expecting a long season, and sow in succession so young plants are always coming on.
Zone 13 covers only the hottest tropical parts of the United States, so these are zone averages, not a promise for any single garden — microclimate, elevation, rainfall and soil all shift the details.
Zone 13 planting data for kale
Published ranges from standard horticultural references — germination and maturity vary by variety, soil and weather, so treat them as guides, not guarantees. Zone 13 is frost-free, with average winter lows above 60°F, so no frost dates appear here: there are none to give.
| Detail | Kale in Zone 13 |
|---|---|
| Germination | 7–10 days |
| Days to maturity | 50–65 days |
| Spacing | 12–18 inches |
| Soil pH | 6.0–7.5 |
| Sun | full sun |
| Sowing method | both |
| Cold tolerance | hardy |
| Water needs | moderate |
| Family | Brassicaceae |
For the wider year, see the planting calendar hub and the cool-season month guides such as January in Zone 13.
Starting kale in Zone 13
Start kale seed indoors or sow directly where it will grow — germination takes 7–10 days either way. Direct sowing is simplest in the cool season: sow into moist soil, thin to the spacing in the table below, and mulch once seedlings are established. Transplanted seedlings give a head start if you sowed late, but harden them off first and transplant in the late afternoon. Sow a few plants every few weeks for a steady supply of young leaves.
Soil, spacing and sun for kale
Kale wants full sun in the cool season — with afternoon shade in the warmer months — and rich, well-drained soil with a pH of 6.0–7.5. Dig in compost before planting; kale is a hungry brassica and poor soil gives tough, bitter leaves. Space plants 12–18 inches apart so air moves between them, mulch to hold moisture, and do not plant where other brassicas grew last season.
Watering kale in Zone 13
Kale has moderate water needs, and steady moisture keeps leaves tender and sweet — drought makes them tough and bitter. Water at the base in the morning, mulch to even out moisture, and in the dry season water deeply a few times a week. In the wet season, drainage matters more than watering. If leaves wilt in midday sun but recover by evening, that is heat, not drought — shade helps more than extra water.
Companion planting for kale
Good companions for kale include marigolds, basil, onions and lettuce. These pairings come from standard companion-planting references. Keep companions low and open so air can move, and avoid planting kale next to other members of the Brassicaceae family in the same season, since they share pests and diseases. For a quick check, try the companion planting finder.
Pests and problems in Zone 13
The common pests for kale are cabbage worms, aphids, flea beetles and slugs. In Zone 13, warm, humid weather means pests and diseases are active all year — there is no winter to knock them back — so check plants every few days and act early. A strong jet of water knocks most aphids off, hand-pick larger pests in the morning, and remove badly infested leaves before a small problem becomes a large one. If damage is severe or you cannot identify the culprit, ask your local extension service — and use the pest identifier helper to narrow it down.
Harvest and storage
Kale takes 50–65 days to maturity, but you do not need to wait that long: start picking outer leaves once plants are big enough to spare them, leaving the centre growing, and the plant keeps producing for weeks. Pick in the morning, when leaves are crisp, and eat young leaves fresh — older leaves are tougher and better cooked. In the heat, harvest young and often, and pull plants once they start to bolt and flower.
Related reading
- Swiss Chard in Zone 13 — another crop from this Zone 13 batch, with the same frost-free timing.
- Kale in Zone 11 — the same crop in a cooler zone, for comparison.
Frequently asked questions
Can you grow kale in Zone 13?
Yes — kale is the most heat-tolerant brassica and does well in the coolest months, roughly December through February, with afternoon shade stretching the season. Zone 13 is frost-free with winter lows above 60°F, so give it shade and steady water in the warmer months.
Why are my kale leaves tough and bitter?
Drought and heat are the usual causes. Keep the soil evenly moist, mulch, give afternoon shade, and pick young leaves often — older leaves are always tougher. Check your local extension service for heat-tolerant varieties.
How do I harvest kale so it keeps growing?
Pick outer leaves, leaving the centre growing. Kale takes 50–65 days to maturity, but you can start picking young leaves earlier and the plant keeps producing for weeks.
How much space does kale need?
Space plants 12–18 inches apart in rich soil. Crowded kale in humid air gets diseased fast, and small plants make small leaves.