Brussel Sprouts Companion Plants

Growing brussel sprouts can be a test of a gardener’s patience, but choosing the right neighbors makes all the difference. Understanding brussel sprouts companion plants is the key to healthier plants and a better harvest. This guide will walk you through the best and worst plants to grow alongside your sprouts, explain the why behind each pairing, and give you practical tips to implement in your garden this season.

Companion planting is more than just an old gardening tale. It’s a strategic way to use plant relationships to your advantage. For brussel sprouts, good companions can deter pests, improve soil nutrients, and even enhance flavor. Let’s look at the plants that make the best teammates for your sprout patch.

Top Companion Plants for Brussel Sprouts

These plants offer clear benefits when planted near your brussel sprouts. They help with everything from pest control to space management.

Aromatic Herbs (Dill, Sage, Thyme, Rosemary, Mint): Their strong scents confuse and repel common pests like cabbage moths and aphids. Be careful with mint—it’s invasive, so plant it in a pot nearby instead of directly in the ground.
Alliums (Onions, Garlic, Chives): These are powerhouse companions. Their pungent smell masks the scent of brussel sprouts from pests. They also help deter cabbage loopers and aphids.
Legumes (Bush Beans, Peas): Beans and peas fix nitrogen from the air into the soil. Brussel sprouts are heavy feeders that love nitrogen, so this gives them a natural nutrient boost.
Root Vegetables (Beets, Celery): These plants occupy a different soil level than the deep roots of brussel sprouts. This means they don’t compete heavily for nutrients and water, making efficient use of space.
Strong-Scented Flowers (Marigolds, Nasturtiums): Marigolds are famous for repelling nematodes in the soil. Nasturtiums act as a “trap crop,” attracting aphids away from your precious sprouts.

Plants to Avoid Near Brussel Sprouts

Just as some plants help, others can hinder. These plants compete too aggressively or attract the same pests.

Other Brassicas (Cabbage, Broccoli, Cauliflower, Kale): They are in the same family and are targeted by the exact same pests and diseases. Grouping them together makes it easy for problems to spread rapidly.
Strawberries: They are heavy feeders and will compete with brussel sprouts for nutrients. Some gardeners also believe they can inhibit the growth of brassicas.
Pole Beans: Unlike bush beans, pole beans can be too competitive. There’s also an old gardening belief that they stunt the growth of brassicas, so it’s best to err on the side of caution.
Tomatoes: They are also heavy feeders and will compete for nutrients. They have different watering needs and can attract pests that might bother your sprouts.

The Science Behind the Pairings

Companion planting works through several natural mechanisms. Knowing these helps you make smarter choices in your garden layout.

Pest Confusion and Repellent

Many insects find their host plants by smell. Strong-scented herbs and alliums mask the scent of the brussel sprouts. This makes it harder for pests like the cabbage white butterfly to find them to lay their eggs.

Trap Cropping

This is a clever strategy. You plant something pests love even more near your main crop. Aphids, for example, often prefer nasturtiums. They’ll swarm the nasturtiums first, leaving your brussel sprouts alone. You can then manage the pests on the sacrificial plants.

Nutrient Sharing and Soil Health

Legumes have a symbiotic relationship with bacteria in their root nodules. These bacteria take nitrogen from the air and convert it into a form plants can use. When the legume plants die back, this nitrogen is released into the soil, benefiting nearby heavy feeders like brussel sprouts.

Spatial Efficiency

This is about using vertical and horizontal space wisely. Low-growing plants like thyme or lettuce can cover the soil around the base of tall brussel sprouts. This acts as a living mulch, suppressing weeds and keeping soil moist. Meanwhile, deep-rooted plants tap into different soil layers.

Planning Your Brussel Sprouts Garden Layout

Putting this knowledge into practice is simple. Follow these steps to design a productive and healthy bed.

Choose Your Spot: Brussel sprouts need full sun—at least 6 hours daily. Ensure the soil is fertile and well-draining.
Map Your Main Crop: Draw your garden bed. Remember, brussel sprouts need space. Plant them 24-36 inches apart in rows that are 30 inches apart. They get big!
Add Nitrogen-Fixers: Plant bush beans or peas in the rows between your brussel sprouts, or in the spaces before the sprouts fill out.
Incorporate Pest Deterrents: Ring the perimeter of your bed with alliums like onions or garlic. Interplant herbs like dill and sage between every few sprout plants.
Use Flowers as Borders: Plant a thick border of marigolds and nasturtiums around the entire bed. This creates a beautiful and functional pest barrier.
Fill Gaps with Shallow Rooters: In the early season, you can plant quick-growing lettuce or spinach between young sprout plants. You’ll harvest them long before the sprouts need the room.

Seasonal Companion Planting Tips

Your companion planting strategy can change as the season progresses to maximize benefits.

Early Spring (At Planting)

When you transplant your brussel sprout seedlings, get your companions in the ground too. Plant onion sets or garlic cloves nearby. Sow seeds for dill, beets, or lettuce between the young plants. This early start helps establish the protective community right away.

Mid-Season (Maintenance)

As the weather warms up, pest pressure increases. This is when your aromatic herbs and flowers really earn their keep. Keep an eye on nasturtiums for aphid infestations. If they get covered, you can remove and dispose of the affected plants to reduce the pest population.

You can also succession plant quick crops like bush beans. Make a second sowing in early summer to ensure a continuous nitrogen benefit. Make sure to water consistently, as stressed plants are more suseptible to pests.

Late Season (Fall Harvest)

Brussel sprouts taste best after a frost. As you wait for harvest, some companions may fade. You can plant a cover crop of clover (a legume) around the base of your plants in late summer. It will protect the soil and add nitrogen for the next season.

Troubleshooting Common Problems

Even with companions, issues can arise. Here’s how to fix them.

Aphids Still Appear: Check your trap crops first. If they’re overwhelmed, spray a strong jet of water on the brussel sprouts leaves to dislodge aphids. Introduce beneficial insects like ladybugs.
Cabbage Worms Seen: Hand-pick them off immediately. If the problem is severe, use floating row covers over your plants from the start to prevent moths from laying eggs. Your aromatic herbs should help, but sometimes they need a little extra assistance.
Plants Seem Stunted: Ensure they aren’t competing with a bad companion. Verify they have enough water and that the soil is rich. A side dressing of compost or a balanced organic fertilizer can give them a boost if legumes aren’t providing enough nitrogen.
Poor Sprout Formation: This is often due to insufficient nutrients or inconsistent watering. Make sure your companions aren’t too thirsty. Mulching around the plants helps retain soil moisture and keeps roots cool.

Beyond Companions: Essential Brussel Sprouts Care

Companion planting is a powerful tool, but it’s not a substitute for good basic care. Here’s what else your brussel sprouts need.

Soil: They thrive in fertile, well-drained soil with a pH between 6.0 and 7.5. Add plenty of compost before planting.
Water: Provide 1-1.5 inches of water per week. Consistent moisture is crucial, especially during sprout formation. Avoid overhead watering to prevent foliar diseases.
Fertilizer: They are heavy feeders. Apply a nitrogen-rich fertilizer when transplanting and again when plants are about 12 inches tall. This supports their extensive leaf growth.
Support: Tall varieties can become top-heavy, especially when loaded with sprouts. Stake plants or hill soil around the base to prevent them from toppling over in wind.

Frequently Asked Questions

Let’s answer some common questions about brussel sprouts and their garden friends.

Can I plant marigolds directly with brussel sprouts?

Yes, absolutely. French marigolds are particularly effective. You can plant them in between your brussel sprout plants or as a dense border around the bed. Their roots release a substance that helps repel harmful nematodes in the soil.

What is the best herb to plant with brussel sprouts?

Dill is often considered one of the best. It attracts beneficial wasps that prey on cabbage worms. Its tall, airy structure also doesn’t compete for space. Sage and thyme are also excellent, low-maintenance choices that provide strong scent protection.

How close should companion plants be?

For herbs and flowers, planting them within 1-2 feet of your brussel sprouts is effective. For alliums, you can intersperse them every square foot or so. The key is to create an intermingled planting, not just a separate row on the side. The scents and root interactions need to be close to work.

Do brussel sprouts need two plants to pollinate?

No, they do not. Brussel sprouts are not grown for their flowers; you harvest the vegetative sprouts. They are typically grown as annuals and will not cross-pollinate in the vegtable garden in their first year. You only need multiple plants if you want a longer harvest.

Can I grow lettuce under brussel sprouts?

Yes, but only as a short-term partner. Lettuce is shallow-rooted and matures quickly. Plant it between young brussel sprout plants in the spring. You will harvest the lettuce long before the sprouts grow large and shade it out. It’s a great way to get an extra crop from your space.

Using companion planting for your brussel sprouts turns your garden into a cooperative ecosystem. By choosing the right friends—like aromatic herbs, alliums, and legumes—you’ll naturally reduce pests, improve soil, and boost your harvest. Avoid planting them with their brassica cousins or heavy competitors like strawberries. Remember, good companions work alongside proper watering, feeding, and care. With this plan, you’re well on your way to a successful season of growing plump, healthy brussel sprouts right in your own backyard.