How to Grow Broccoli in Raised Beds: A Complete Step-by-Step Guide

Introduction

Broccoli is a nutritious and versatile vegetable that’s ideal for growing in raised beds. With its crisp texture, rich flavour, and high vitamin content, it’s a favourite among gardeners who want to enjoy fresh produce from plot to plate. If you’re wondering how to grow broccoli in raised beds, you’re in the right place.

This comprehensive step-by-step guide will walk you through everything—from choosing the right varieties and preparing your raised bed to sowing, caring, and harvesting for the best yield possible.

Why Grow Broccoli in Raised Beds?

🌱 Improved drainage and soil quality – Raised beds prevent waterlogging and allow easy soil improvement.
🌿 Better pest control – Raised beds are easier to net and protect from pests.
🔄 Efficient crop rotation – Manage crop families more effectively in designated bed systems.
🪴 Space-saving – Raised beds help organise your garden, especially in small spaces.
🥦 Higher yield – Better soil control and less compaction support healthier plants.

Best Broccoli Varieties for Raised Beds (UK)

Variety	Type	Harvest Time	Notes
Calabrese Ironman	Calabrese	Summer to early autumn	Fast-growing, good for raised beds
Belstar F1	Calabrese	Summer	Compact, ideal for smaller raised beds
Claret F1	Purple sprouting	Late winter to spring	Hardy and high-yielding
Red Arrow	Purple sprouting	Late winter to spring	Excellent flavour, cold-tolerant
Santee	Purple sprouting	Autumn to winter	Early sprouting variety

Tip: Grow both Calabrese and purple sprouting varieties for harvests across multiple seasons.

When to Plant Broccoli in the UK

Task	UK Timing
Sow indoors (Calabrese)	February to April
Sow outdoors	March to May
Transplant outdoors	April to June
Harvest (Calabrese)	June to October
Sow purple sprouting	March to May (for winter cropping)
Harvest (Purple Sprouting)	January to May

Step-by-Step: How to Grow Broccoli in Raised Beds

Step 1: Choose the Right Location

Broccoli thrives in:

Full sun
Sheltered sites protected from strong winds
Firm, fertile, and well-drained soil

Raised beds are ideal because they warm up earlier in spring, offer excellent drainage, and allow for easier soil enrichment.

Step 2: Prepare the Soil in Raised Beds

Broccoli is a heavy feeder and prefers a neutral to slightly alkaline soil (pH 6.5–7.5).

Soil Preparation:

Fill the raised bed with quality topsoil mixed with compost or well-rotted manure.
Add a base dressing of general-purpose fertiliser (e.g., Growmore or blood, fish, and bone).
Firm the soil with the back of a rake—broccoli prefers solid ground to prevent root disturbance.

Tip: Add garden lime if your soil is acidic—broccoli is a brassica and prefers alkaline conditions.

Step 3: Sowing Broccoli Seeds

Indoor Sowing:

Sow seeds from February to April in seed trays or modules.
Sow 1cm deep and keep at 15–18°C.
Transplant when seedlings have 4–6 true leaves.

Outdoor Sowing:

Sow directly into a separate seed bed in March to May.
Thin seedlings to 5–7cm apart.
Transplant to raised beds when around 15cm tall.

Step 4: Transplanting into Raised Beds

Transplant seedlings when the risk of frost has passed.

How to Transplant:

Space plants 40–60cm apart, depending on the variety.
Water plants well before transplanting.
Dig a hole deep enough to bury the seedling up to the first leaves.
Firm the soil well around the base and water again.

Pro Tip: Use cabbage collars to prevent cabbage root fly.

Caring for Broccoli in Raised Beds

1. Watering

Water regularly, especially during dry spells.
Avoid waterlogging—raised beds should drain well.
Water at the base, not on the leaves, to avoid fungal issues.

2. Feeding

Once heads start forming, feed weekly with a high-potash fertiliser like tomato feed.
You can also top-dress with compost mid-season.

3. Weeding and Mulching

Keep the bed weed-free.
Apply a mulch of compost or straw to retain moisture and regulate soil temperature.

4. Support

In windy areas, support large-headed varieties with canes.

Protecting Broccoli from Pests

Raised beds make pest control easier, but vigilance is key.

Pest	Signs	Control
Cabbage white butterfly	Holes in leaves, caterpillars present	Use fine mesh netting or fleece
Cabbage root fly	Plants wilt or collapse	Use collars around the base of plants
Slugs and snails	Ragged holes in young leaves	Apply slug pellets, traps, or barriers
Aphids	Sticky residue, curled leaves	Wash off with water or use organic spray
Clubroot	Swollen, distorted roots	Avoid acidic soils, rotate crops

Harvesting Broccoli for Best Yield

When to Harvest:

Calabrese: When central head is firm and tight, about 10–20cm across
Purple sprouting: When small florets appear on side shoots

How to Harvest:

Cut the main head with a sharp knife.
Leave the plant in the ground—it will produce smaller side shoots for a secondary harvest.
For purple sprouting, cut tender shoots when buds are tight (before they flower).

Storing and Using Broccoli

Short-Term Storage:

Keep in the fridge for up to 5 days in a sealed bag.

Freezing Broccoli:

Wash and chop into florets.
Blanch in boiling water for 2–3 minutes.
Cool quickly in ice water, drain, and freeze in airtight bags.

Growing Broccoli Successionally for Longer Harvests

To enjoy broccoli over several months:

Sow in small batches every 2–3 weeks between February and May.
Mix varieties—early Calabrese, late autumn, and overwintering purple sprouting types.
Use cold frames or cloches to extend the growing season into early spring and late autumn.

Companion Planting for Broccoli

Good Companions:

Onions – Help deter pests
Beets – Don’t compete for nutrients
Celery – Improves soil health

Avoid Planting Near:

Strawberries – Compete for nutrients
Tomatoes – Prefer different growing conditions
Other brassicas – Rotate crops to avoid soil-borne disease

Crop Rotation and Aftercare

Broccoli is part of the brassica family—don’t plant it in the same spot more than once every 3 years.
Follow with legumes (peas, beans) to restore nitrogen levels.
At the end of the season, remove old plants, compost healthy ones, and dig in soil amendments.

Conclusion

Growing broccoli in raised beds is one of the smartest ways to get a delicious, healthy, and reliable crop from your garden. With good preparation, consistent care, and the right protection, you can enjoy bountiful harvests of fresh broccoli for months—whether you’re tucking into summer Calabrese or harvesting frosty purple sprouting shoots in February.

Follow the steps in this guide, and your raised beds will be bursting with big green heads and tender shoots, ready to go from garden to plate.