Brussels Sprouts in Zone 8B — Southeast

Brussels sprouts are a rewarding addition to the Southeast garden, offering a unique, nutty flavor that's delicious roasted, sautéed, or shredded in salads. Their cold hardiness means you can enjoy a fresh harvest even as the temperatures dip, a welcome treat after our long summer. There's a real satisfaction in growing your own, especially when they taste so much better than what you find at the grocery store.

Our hot and humid summers, along with common pests like Japanese beetles, can pose challenges to growing Brussels sprouts. However, by starting early and choosing the right varieties, you can easily navigate these hurdles and make the most of our 255-day growing season. Timing is everything in the Southeast.

Here in the Southeast, starting Brussels sprouts indoors gives them a head start before the heat kicks in. Sow your seeds from mid January through early February, about six weeks before you plan to transplant them into the garden. A basic seed starting setup with seed trays, a heat mat, and grow lights will do the trick.

Bottom watering is key to preventing damping off. Pour water into the tray beneath your seed cells and allow the soil to soak it up from the bottom. With our moderate springs, this helps maintain consistent moisture without overwatering.

Transplant your Brussels sprouts seedlings outdoors in early to late March. Be sure to harden them off first by gradually exposing them to outdoor conditions for about a week. This helps them adjust to the sunlight and temperature fluctuations.

Space your plants 18-24 inches apart in rows. Keep an eye on the weather forecast, as we can still get some unexpected cold snaps this time of year. Covering your young plants with frost cloth will protect them if temperatures dip below freezing.

Brussels sprouts need consistent moisture to develop those tight, flavorful sprouts we all crave. Aim for about 1-1.5 inches of water per week, especially during dry spells. Our summers are known for afternoon thunderstorms, but don't rely solely on rainfall; check the soil moisture regularly.

Stick your finger about two inches deep into the soil near the base of the plant. If it feels dry, it's time to water. Watering at the base of the plant is best to avoid wetting the foliage, which can encourage fungal diseases in our humid climate.

Signs of underwatering include wilting leaves and loose, open sprouts. Overwatering, on the other hand, can lead to yellowing leaves and root rot. A good layer of mulch around your plants will help retain moisture and suppress weeds, which is especially important with our clay soil.

Brussels sprouts can get quite tall and top-heavy, especially when those sprouts start to fill out. Staking them is a must, especially with the strong winds we sometimes get during thunderstorm season. Bamboo stakes or sturdy tomato cages work well.

Install the support when the plants reach about two feet tall to prevent them from toppling over. Gently tie the main stem to the stake with soft twine or plant ties. As the plant grows, continue to add additional ties as needed.

Pruning Brussels sprouts is fairly straightforward. As the sprouts develop from the bottom up, remove the yellowing or damaged lower leaves. This improves air circulation and directs the plant's energy towards sprout production.

About three to four weeks before your expected harvest, top the plant by cutting off the top set of leaves. This encourages the remaining sprouts to mature more quickly. As our first frost approaches around mid- November, you can harvest any remaining sprouts, even if they're small, as their flavor will improve with a touch of frost.

Here in the Southeast, you can expect your first Brussels sprouts harvest from early June through mid July, about 90 days after transplanting. The sprouts are ready to pick when they are firm, tight, and about 1-2 inches in diameter. Harvest from the bottom of the stalk upwards, twisting or cutting the sprouts off cleanly.

Regular harvesting encourages the plant to continue producing new sprouts higher up the stalk. Don't be afraid to harvest after a light frost; in fact, many gardeners believe that a touch of frost improves the flavor of Brussels sprouts, making them sweeter and less bitter.

As our first frost approaches around mid- November, harvest any remaining sprouts, even if they are small. You can also cut the entire stalk and hang it upside down in a cool, dark place for longer storage.

Here are some common problems you might encounter with Brussels sprouts in the Southeast:

Aphids *What it looks like:* Clusters of tiny soft-bodied insects (green, black, or white) on stems and leaf undersides. Sticky honeydew residue. Curled or distorted new growth. *What causes it:* Rapid-reproducing sap-sucking insects. Populations explode in warm weather. Ant colonies may farm them for honeydew. *How to fix/prevent it:* Strong water spray knocks them off. Encourage ladybugs and lacewings (natural predators). Insecticidal soap for heavy infestations. Neem oil works systemically. Avoid excess nitrogen fertilizer (it attracts them).

Cabbage Worms *What it looks like:* Smooth green caterpillars on brassica leaves. Irregular holes chewed in leaves. Dark green droppings. White butterflies hovering around plants. *What causes it:* Larvae of white cabbage butterflies. Multiple generations per season in warm climates. *How to fix/prevent it:* Bt spray is very effective. Floating row covers prevent egg laying. Handpick caterpillars. Interplant with aromatic herbs (thyme, sage). Encourage parasitic wasps.

Loose Sprouts from Heat *What it looks like:* Sprouts that are not tightly formed, but rather loose and leafy. They may also taste bitter. *What causes it:* High temperatures during sprout development. The plant struggles to form tight sprouts in the heat. *How to fix/prevent it:* Choose heat-tolerant varieties. Provide afternoon shade during the hottest part of the day. Ensure consistent watering to prevent stress. Plant for a fall harvest to avoid the worst of the summer heat.

Clubroot *What it looks like:* Stunted growth, wilting in afternoon heat, yellowing leaves. Roots are swollen, distorted, and club-shaped when dug up. *What causes it:* Soil-borne pathogen (Plasmodiophora brassicae) that persists in soil for 10+ years. Favors acidic, wet soil. *How to fix/prevent it:* Raise soil pH to 7.0-7.2 with lime. Improve drainage. Rotate brassicas on a 7-year cycle. Remove and destroy infected plants (don't compost). Start transplants in sterile mix.

Southeast Specific Challenges: Our hot and humid summers create a perfect environment for fungal diseases, so ensure good air circulation and avoid overhead watering whenever possible. Japanese beetles can also be a nuisance, so consider using row covers or handpicking them off the plants. Deer are a common problem in many areas, so fencing or deer repellent may be necessary to protect your Brussels sprouts.

Companion planting can give your Brussels sprouts a boost in the Southeast garden. Green beans fix nitrogen in the soil, benefiting the nutrient-hungry sprouts. Celery and onions deter pests, while dill attracts beneficial insects like ladybugs and lacewings. Potatoes don't directly benefit the sprouts, but they don't compete for the same nutrients and can help break up our heavy clay soil.

Avoid planting Brussels sprouts near tomatoes, strawberries, or peppers. These plants can attract similar pests and diseases, increasing the risk of problems. Plus, tomatoes can stunt the growth of brassicas.