How to Grow Broccoli

Growing guide

Overview

Broccoli is a cool-season vegetable grown for its tender, nutrient-dense heads. Gardeners value it because it produces a main head plus weeks of side shoots, and it’s safe around dogs and cats. It needs full sun, moderate water, and consistent moisture to thrive.

Soil & planting prep

Broccoli grows best in loamy or clay soil that drains well, with a pH between 6.0 and 7.0. Work in 2–3 inches of compost before planting. Space plants 18–24 inches apart, setting them at the same depth they were growing in the pot.

When to plant

For a spring crop, start seeds indoors 6 weeks before your last frost date and transplant seedlings 2–3 weeks before that last frost, once they have 4–5 true leaves. For a fall crop, direct sow or transplant in midsummer, about 10–12 weeks before your first fall frost. Broccoli is frost-tolerant and can handle light freezes, but it bolts in heat, so time your crop to mature in cool weather.

How to plant

1. Start seeds indoors 6 weeks before last frost in seed-starting mix, keeping soil at 65–75°F.
2. Harden off seedlings over 7–10 days by gradually exposing them to outdoor conditions.
3. Prepare the bed with compost and ensure it drains well; broccoli rots in waterlogged soil.
4. Transplant seedlings 18–24 inches apart, burying the stem up to the first set of leaves.
5. Water deeply after planting and keep soil evenly moist with 1–1.5 inches of water per week.

5 common mistakes to avoid

• Planting too late in spring so heads mature in hot weather, causing bolting and bitter, loose heads—start seeds early and transplant while nights are still cool.
• Letting the soil dry out, which stresses plants and produces small, tough heads—water consistently, especially when heads are forming.
• Crowding plants closer than 18 inches, which reduces airflow and invites disease—give each plant full spacing.
• Harvesting the main head too late, after yellow flowers begin to open, which stops side-shoot production—cut while buds are tight and green.
• Skipping fall planting in warm regions, where spring crops often fail—sow a fall crop in midsummer for the best heads.

Harvesting & storage

Harvest the main head when it is firm and tight, before any yellow flowers open, cutting the stem about 5–6 inches below the head. Side shoots will keep producing for weeks; cut them when they are 3–4 inches across. Store broccoli in a plastic bag in the refrigerator for up to a week.

Companion planting

Good companions include onions, garlic, and aromatic herbs like dill and rosemary, which may help repel pests. Avoid planting broccoli near tomatoes or strawberries, as they can compete for nutrients and share pests.

Growing in containers

Broccoli can be grown in containers at least 5 gallons in size, using a well-draining potting mix. Keep it in full sun and water regularly, as container soil dries out faster than garden soil.

Pro tips

Start indoors 6-8 weeks before last frost for spring planting or direct sow in midsummer for fall. Harvest the main head before it flowers — side shoots continue producing after.