Sowing and Growing Brussels sprouts

Why Grow Brussels Sprouts

While Brussels sprouts may not quite match the appeal of Kalettes, they score highly across almost every category, making them an excellent choice for gardeners.

1. Taste Appeal: Many people love Brussels sprouts. For those who don’t, it’s interesting to note that most enjoy the leaves and tops.
2. Nutritional Value: These sprouts are incredibly healthy, comparable to kale and cabbage.
3. Market Pricing: While sprouts are relatively cheap in shops, their leaves and tops are rare and delightful.
4. Exceptional Harvest: When grown as described in this guide, Brussels sprouts yield remarkably during the hungry gap, offering lush leaves and perfect loose leaf cabbage-like tops in early summer. The early sprouts become a mid-summer delight, and this process can be repeated for a second harvest through to March.
5. Pest Management: Like kale, Brussels sprouts may often be treated with pesticides to manage pests like caterpillars, cabbage aphids, and whiteflies.

How Many to Grow?

For spring leaf harvesting, Wellies and Waxjackets recommend growing one plant per person. If growing for sprouts, the number depends on personal preference. Under ideal conditions, a single Brussels plant can yield enough for one person for about a month, with an average harvest span of three months. Thus, three plants per person is advisable, occupying roughly 0.7m² per individual.

When to Sow Brussels

To maximise yields, two or three sowings are suggested, categorised as follows:

1. First Earlies: Sow in mid-autumn to harvest leaves by May.
2. Main Crop: Sow in mid-March for a late autumn harvest.
3. Late Crop: Sow in May to harvest in winter.

More Details:

1. Seed Sowing: Without grow lights, sow about 24 plants in late September or early October, keeping in mind that winter growing conditions can be unpredictable. Germination indoors followed by cold greenhouse growth is ideal.
2. With Grow Lights: Grow lights allow for confident sowing in late November, keeping plants under lights for approximately six weeks.
3. February Planting: If using a polytunnel or similar structure, plants should be planted out in February after a week of frost-free weather. Harden them off gradually before planting if necessary.
4. Main Crop Sowing: Mid-March is optimal for main crop sowings, although some might suggest a late June crop to allow for earlier spring harvesting from the same bed.

Favourite Varieties

Wellies and Waxjackets offer various varieties to choose from to suit different gardening needs.

How to Sow Brussels

Brussels sprouts are sown similarly to other brassicas. Start by filling pots with compost, levelling the surface, sprinkling seeds evenly, and covering with 1cm of compost. Germinate indoors at around 18°C, with sprouts expected to emerge in about a week.

How to Prick Out Brussels

Seedlings should be pricked out when 1-2 inches tall, ideally before developing true leaves. Using a small screwdriver, gently ease them from the compost, holding them by the leaves, and plant them deep into the new compost.

For optimal growth, use potting compost in a six-cell module tray to provide ample nutrition until planting.

Where to Plant Brussels

Brussels thrive in full sun and slightly alkaline soil enriched with well-rotted manure, poultry pellets, and compost. Their growth requires ample nitrogen, more so than cabbages and Kalettes. Slow-release nitrogen sources, like hoof and horn, are recommended to sustain their needs over the growing period.

Preparing the Ground for Brussels

Ground preparation mirrors that of other brassicas:

1. Cover Crops: Plant field beans in the brassica bed over winter for added nutrients.
2. Soil Firmness: Ensure the ground is firm, tamping down gently.
3. Soil Moisture: Water the soil a few days prior to planting.
4. Soil Amendments: Depending on soil needs, apply lime or poultry manure.
5. Mulching: A 1-2 inch layer of spent mushroom compost is ideal for moisture retention and weed suppression.

How to Plant Brussels

Planting for Hungry Gap Leaves

Brussels can be densely planted for leaf harvesting. A range of 18 to 27 plants per square metre is suggested, with a typical yield of 12 thriving plants.

Planting occurs in February when plants are about 6-8 inches tall. Early planting encourages root establishment before the growing season.

Planting Main Crop for Winter

Brussels should be spaced 70-80cm apart, allowing for creative interplanting. Red cabbages make an excellent companion crop.

Plant in early or late May, ideally after the last frost, with plants measuring 8-10 inches tall.

Key Planting Considerations:

1. Water Treatment: Water modules with nematode solutions before planting to combat root fly.
2. Leaf Inspection: Check leaves for pests before planting.
3. Ground Firmness: Ensure soil is firm before planting.
4. Planting Depth: Ensure exposed stems are buried to encourage deep rooting.
5. Nutrient Addition: Add concentrated manure or hoof and horn into planting holes.
6. Watering: Water the hole thoroughly before planting.
7. Mulching: Apply mushroom compost around plants for weed control.
8. Netting: Protect plants with netting to deter pests.

Watering

The key is to water thoroughly but infrequently, allowing roots to establish before subsequent watering. Nematodes can be reapplied after two weeks if conditions allow.

Supporting the Plants

Due to their height and foliage, Brussels can be vulnerable to wind. Wellies and Waxjackets recommend using fence pins to support netting, ensuring plants remain upright and healthy.

To Net or Not to Net?

Through trial and error, Wellies and Waxjackets have found that using nets can prevent pigeons from damaging plants while allowing beneficial predators to access the crops. A butterfly net is recommended for this reason.

Nets are typically removed in July, allowing for close monitoring of pests.

Cold Weather

Brussels are hardy and can withstand winter conditions. However, they may require more clean-up during winter harvesting compared to kalettes, which tend to sweeten after frost.

How to Harvest Brussels

The harvesting period for Brussels spans from May to April. Initially, leaves are harvested, followed by sprout tops in July, which stimulates further sprout development.

By October/November, the first sprouts will mature, and it’s essential to harvest them promptly to encourage more growth.

In late winter, leave any lower-quality sprouts on the plant for potential further growth, resulting in a delightful spring harvest.

Post Harvest

After harvesting, Brussels are washed thoroughly to remove pests and debris. They are soaked in cold water to refresh them and can be stored in airtight containers for up to a week.

How to Cook Sprouts

Wellies and Waxjackets recommend lightly steaming Brussels sprouts, but there are many culinary options available for those looking to try something different.

How to Deal with Pests

Brussels sprouts can be more prone to pests than other brassicas. The cabbage aphid is a common issue, but effective management strategies can help mitigate damage:

1. Initial Ignoring: Early aphid sightings may be ignored.
2. Monitoring and Removal: As populations grow, infested leaves can be removed or plants washed with water.
3. Soapy Water Treatment: If infestations escalate, a soapy water spray may be used.
4. Preventive Measures: Regular monitoring and cleaning will keep plants healthy.