Cabbage in Zone 7A — Mid-Atlantic

Cabbage is a fantastic addition to any Mid-Atlantic garden. Its crisp, slightly sweet flavor is a welcome treat, especially after our cold winters. Plus, Cabbage is incredibly versatile in the kitchen, lending itself well to everything from slaws to stir-fries.

Our humid summers and variable spring weather can present some challenges, but with careful timing and a little attention, you can easily grow beautiful heads of Cabbage during our 208-day growing season. We'll help you navigate the specifics to get the best results.

Starting Cabbage indoors gives you a head start, especially for a spring harvest. Begin sowing your seeds indoors from early to late February, about six weeks before you plan to transplant them outdoors. This helps you dodge the late frosts we sometimes see.

Use seed trays or small pots filled with a good seed-starting mix. Keep the soil consistently moist, and consider bottom watering to avoid damping off – just set the tray in a shallow dish of water and let the soil absorb it from below. Place the trays in a warm spot and provide plenty of light, either with a grow light or in a bright, south-facing window. Our moderate spring means seedlings need all the help they can get!

Transplant your Cabbage seedlings outdoors from late March through mid April, once the danger of hard frost has passed. Before planting, harden off your seedlings by gradually exposing them to outdoor conditions for about a week. Start with an hour or two of shade, increasing the time and sun exposure each day.

Space your plants 12-18 inches apart in rows. Be prepared to cover them if a late cold snap threatens. Our springs can be unpredictable, so keep an eye on the forecast!

Cabbage needs consistent moisture to thrive, but overwatering can be just as detrimental, especially with our humid summers. Aim for about 1 inch of water per week, including rainfall. You might need to supplement during drier periods.

The finger test is a good way to gauge soil moisture. Stick your finger into the soil about 2 inches deep. If it feels dry, it's time to water. Water at the base of the plant to avoid wetting the leaves, which can encourage fungal diseases in our humid climate. Overhead watering is fine on occasion, but try to do it in the morning so the leaves have time to dry.

If the leaves are wilting and the soil is dry, your Cabbage is likely underwatered. Yellowing leaves and soggy soil indicate overwatering. A layer of mulch, like straw or shredded leaves, will help retain moisture and suppress weeds, which is a big help during our moderately hot summers.

You can expect your first harvest of Cabbage from late May through mid July, about 70 days after transplanting. The key is to check the firmness of the head. It should feel solid and dense when you squeeze it.

To harvest, use a sharp knife to cut the head at its base, leaving a few outer leaves intact. As our first frost approaches in late October, harvest any remaining heads, even if they aren't quite fully mature. They'll still be delicious!

Here are some common problems you might encounter growing Cabbage in the Mid-Atlantic:

Cabbage Worms

• What it looks like: Smooth green caterpillars munching on leaves, leaving irregular holes and dark green droppings behind. You'll often see white butterflies fluttering around.
• What causes it: These are the larvae of cabbage butterflies, and we often have multiple generations throughout our warm season.
• How to fix/prevent it: Bt (Bacillus thuringiensis) spray is very effective. You can also use floating row covers to prevent the butterflies from laying eggs in the first place. Handpicking caterpillars is also an option. Interplanting with aromatic herbs like thyme and sage can help deter them, and encouraging parasitic wasps can keep their populations in check.

Cabbage Loopers

• What it looks like: Similar to cabbage worms, but these caterpillars move in a looping motion. They also chew holes in leaves.
• What causes it: These are a different type of caterpillar that thrives in our warm, humid summers.
• How to fix/prevent it: Bt spray works well on cabbage loopers too. Handpicking and row covers are also effective.

Splitting

• What it looks like: The Cabbage head cracks open.
• What causes it: Inconsistent watering. A sudden heavy watering after a dry spell causes the head to swell too quickly, leading to splitting. This is common after summer thunderstorms.
• How to fix/prevent it: Water regularly and consistently. Mulch helps retain moisture. If a heavy rain is predicted after a dry spell, consider lightly scoring the base of the head with a knife to relieve pressure.

Clubroot

• What it looks like: Stunted growth, wilting in the afternoon heat, and yellowing leaves. When you dig up the plant, the roots are swollen, distorted, and club-shaped.
• What causes it: A soil-borne pathogen that persists for years, especially in acidic, wet soil.
• How to fix/prevent it: Raise the 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 them!). Start transplants in a sterile mix to avoid introducing the pathogen.

Mid-Atlantic Specific Challenges: Our moderate-to-hot summers and humid climate create ideal conditions for pests and diseases that love brassicas. Consistent monitoring and proactive measures are key to keeping your Cabbage healthy.

Good companions for Cabbage in the Mid-Atlantic include green beans, celery, onions, potatoes, and dill. Green beans fix nitrogen in the soil, which benefits Cabbage. Celery and onions deter pests, while potatoes help to break up our often-heavy clay soil. Dill attracts beneficial insects that prey on Cabbage pests.

Avoid planting Cabbage near tomatoes, strawberries, and peppers. Tomatoes and peppers compete for the same nutrients. Strawberries are susceptible to diseases that can also affect Cabbage.