Collard greens are the hardy leafy green that Zone 7 grows best in autumn — frost-sweetened, long-lasting and generous all winter. This guide covers when to plant collard greens zone 7 in detail: the sowing, transplanting and harvest windows for USDA Zone 7, plus spacing, soil, water, companions, pests and storage — all based on USDA zone averages and standard published crop ranges.
Zone 7 covers areas with average annual minimum temperatures of 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 — check your local extension service and the forecast before planting tender crops outside. The frost-free season runs roughly seven months, from late March into early November,
When to plant collard greens in Zone 7
Collards can be sown in spring, but in Zone 7 the autumn crop is the star. Start seed indoors in February to March for a spring crop, or — better — sow in August to September for plants that mature into the cool days of autumn, when a touch of frost sweetens the leaves. Germination takes 7–10 days.
The table below puts the whole season on one page. All dates are ranges worked back from the Zone 7 frost averages (Mar 15–Apr 1 last frost, Nov 1–15 first frost) and the crop's published days to maturity (60–80 days). Use the frost date calculator to check the averages for your own area, and confirm them with your local extension service.
| Stage | Zone 7 window | Notes |
|---|---|---|
| Start indoors | Feb–Mar for spring; June–July for autumn | Germination takes 7–10 days |
| Direct sow outdoors | Mar–Apr, and Aug–Sep for the autumn crop | Sow into moist, prepared soil |
| Transplant outdoors | Apr, and Sep for autumn plants | Harden seedlings off first |
| First harvest | May–June and Oct–Dec, 60–80 days after sowing | 60–80 days to maturity |
| Autumn / second sowing | The autumn crop is the best in Zone 7 — sow Aug–Sep | Count back from the first frost |
Starting and planting
Space plants 12–18 inches apart in rows about 2 feet apart, in rich soil with a pH of 6.0–7.5. Collards are heavy feeders, so dig in compost and feed through the season. Keep them watered in dry spells and mulch thickly; a well-grown collard plant is a large, handsome thing that feeds a family for months.
Before sowing, fork the bed over, remove weeds and stones, and dig in well-rotted compost. Collard Greens grows best at a soil pH of 6.0–7.5 — test your soil through your local extension service before amending it.
Spacing, sun and soil
Space plants 12–18 inches apart. Crowded plants compete for light, water and nutrients, stay small, and invite disease through poor airflow, so thin seedlings to the final spacing once they are established.
This crop needs full sun — at least six hours of direct sun a day, and more is better. In Zone 7, a south-facing bed or an open spot away from trees and fences gives the strongest growth and the best flavour.
Soil should be deep, fertile and free-draining, with a pH of 6.0–7.5. Heavy clay improves with compost and organic matter, and raised beds help where drainage is poor.
Watering
Water needs are moderate: aim for steady, even moisture rather than feast-and-famine watering. About an inch of water a week from rain or irrigation is a useful guide in most Zone 7 summers, more in hot, dry spells. Water at the base of the plant in the morning, mulch to hold moisture, and avoid wetting the leaves, which invites disease.
Companion planting
Good companions for collard greens include marigolds, basil, onions, lettuce. Planting companions nearby can help with pest confusion, pollination and making the most of bed space — marigolds, for example, are a classic companion across the vegetable garden. The companion planting finder can suggest combinations for your whole bed. Avoid planting collard greens where others of the same family (Brassicaceae) grew last year: rotate crops each season to reduce soil-borne disease and pest build-up.
Common pests and problems
Watch for cabbage worms, aphids, flea beetles, slugs. - Cabbage Worms — inspect weekly; hand-pick or wash off with water, and encourage natural predators.
- Aphids — inspect weekly; hand-pick or wash off with water, and encourage natural predators.
- Flea Beetles — inspect weekly; hand-pick or wash off with water, and encourage natural predators.
- Slugs — inspect weekly; hand-pick or wash off with water, and encourage natural predators.
Beyond pests, the main problems are weather-related: a late frost after transplanting, drought at a critical stage, or waterlogged soil after heavy rain. Cover tender plants with frost cloth if a late frost threatens, and mulch to even out soil moisture.
Harvest and storage
Pick outer leaves as needed from May to June for spring plants, and from October into December for autumn plants — 60–80 days after sowing. Leaves taste best after a light frost, and the plants stand through winter in most of Zone 7 under a light mulch.
Collards keep for a week or more in the fridge, and blanched leaves freeze well. Best of all, autumn plants can simply be left in the ground and picked through winter, storing themselves in the bed.
The classic Zone 7 mistake with collard greens is treating them as a spring-only crop. Summer heat makes them tough and bitter — the autumn sowing, maturing into cool weather, is where collards truly shine.
Frequently asked questions
When should I plant collard greens in Zone 7?
Collards can be sown in spring, but in Zone 7 the autumn crop is the star. Work from the table above, using the average last frost (Mar 15–Apr 1) and first frost (Nov 1–15), with 60–80 days to maturity. These are USDA zone averages, not exact dates for any one garden — check your local extension service and the forecast before planting tender crops outside.
How much sun does collard greens need in Zone 7?
Full Sun — at least six hours of direct sun a day where possible. Give it the sunniest spot you have.
What soil pH does collard greens prefer?
A pH of 6.0–7.5. Test your soil before amending it, and add compost to improve structure whatever the pH. Your local extension service can test a sample and recommend amendments.
What pests attack collard greens in Zone 7?
The most common are cabbage worms, aphids, flea beetles, slugs. Inspect plants weekly, hand-pick larger pests, wash small ones off with water, and keep the bed clean and well-spaced so air circulates.
How do I store collard greens after harvest?
Collards keep for a week or more in the fridge, and blanched leaves freeze well. Best of all, autumn plants can simply be left in the ground and picked through winter, storing themselves in the bed.
See the Zone 7 September planting guide for what else to sow and plant in the same month, browse the full planting calendar, and try the Harvest Date Calculator to plan your dates. For a related crop, see when to plant brussels sprouts in Zone 7.