When to Harvest Broccoli

When to Harvest Broccoli: Your Expert Guide to a Perfect UK Crop

Timing your broccoli harvest is key to achieving sweet, firm heads and encouraging continued cropping throughout the season. In the UK, understanding when to cut makes all the difference between a crisp, tasty harvest and a bitter, over-mature crop.

Broccoli is one of the most rewarding brassicas to grow, offering harvests from summer right through to the following spring depending on the variety. Whether you’re growing Calabrese for large, dense heads or Sprouting Broccoli for an extended spring yield, getting the timing right is essential for the best flavour and results.

Broccoli Harvest Overview

When is Calabrese Ready to Harvest?

Calabrese is the classic “supermarket-style” broccoli – a single, large head that’s usually ready in late summer or early autumn. Harvest too late and the buds will open, affecting taste and texture. Use the points below to spot the perfect time to cut.

• Look for Tight Buds: The head should be a rich, deep green and the flower buds tightly closed and firm to the touch.
• Optimal Size: Usually about the size of a cricket ball when ready, though this varies between cultivars. Check your seed packet for exact maturity timing.
• Harvest Before Yellowing: If the buds begin to loosen or show any yellow petals, harvest immediately to prevent bitterness and loss of flavour.

How to Harvest Calabrese for Continued Cropping

• The First Cut: Use a sharp knife or secateurs to remove the central head, taking 12–15cm of stem. Make a slanted cut to prevent water collecting on the stump.
• Encouraging Side Shoots: Once the main head is removed, the plant redirects energy into smaller, tender side shoots which are perfect for a second harvest.
• Ongoing Harvest: Keep plants well-watered and fed. Side shoots will form within 4–6 weeks and can be picked regularly before the buds open.

When is Sprouting Broccoli Ready to Harvest?

Sprouting broccoli, available in both purple and white varieties, is one of the most valuable crops for the UK grower. It thrives in cool weather, providing fresh produce when little else is available.

• Look for: Spears that are well-formed and firm but before any flowers open. Typically 10–20cm long when ready.
• Harvesting Technique: Cut or snap off the central spear first to encourage more side shoot growth.
• Extended Cropping: Once established, plants can produce for up to eight weeks, offering continuous harvests throughout late winter and spring.

Advanced Grower Tips: Maximising Flavour and Yield

• Harvest Early in the Day: Pick in the cool of the morning when heads are firm and crisp for the best flavour and texture.
• Pest Protection: Broccoli is a brassica favourite for pigeons and cabbage white caterpillars. Use fine mesh or netting from planting out to protect your plants.
• The Bolting Battle: Broccoli prefers cooler conditions. During hot UK spells, ensure consistent watering and apply mulch to keep soil cool and moist, reducing the risk of early flowering.
• Don’t Waste the Leaves: Broccoli leaves are nutrient-rich and delicious. Use young leaves raw in salads or cook larger ones like kale or collard greens.

Summary: Harvesting Broccoli in the UK

For the best results, keep a close eye on your plants and harvest promptly when buds are tight and firm. Calabrese offers a quick summer harvest with the bonus of side shoots later in the season, while sprouting broccoli provides a reliable supply through the colder months. With the right timing and care, you can enjoy fresh, home-grown broccoli nearly all year round.