Collard Greens in Zone 6A — Mid-Atlantic

Here in the Mid-Atlantic, Collard Greens are a fantastic addition to any garden. The flavor is amazing, especially after a kiss of frost, and they’re incredibly versatile in the kitchen. Plus, there's a real satisfaction in harvesting your own greens well into the fall, long after many other crops have called it quits, thanks to their cold hardiness.

Our Mid-Atlantic climate, with its humid summers and variable spring weather, can present some challenges. But with careful timing, you can easily work around these issues and enjoy a bountiful harvest of Collard Greens within our 188-day growing season.

Starting Collard Greens indoors isn't strictly necessary here in the Mid-Atlantic, but it can give you a head start, especially if you're aiming for an early harvest. If you want to go this route, start your seeds indoors from about mid-March through early April, roughly four weeks before you plan to transplant them outside.

Use seed trays or small pots filled with a good seed-starting mix. Keep them warm and provide plenty of light – a sunny windowsill or a grow light works well. Don't forget to water from the bottom to encourage strong root growth and prevent damping-off. With our moderate spring, you'll have healthy seedlings ready to go out as soon as the weather cooperates.

Transplant your Collard Greens seedlings outdoors from mid-April through mid-May, after the risk of a hard frost has passed. Before planting, harden them off by gradually exposing them to outdoor conditions for about a week. This helps them adjust to the sunlight and temperature changes.

Space your plants about 18-24 inches apart to give them room to grow. Keep an eye out for late frosts that can still pop up during this time, and be prepared to cover your seedlings if necessary.

Direct sowing is a perfectly viable option for Collard Greens here in the Mid-Atlantic, and it's often the easiest. Sow your seeds directly into the garden from early April through late July. You'll get slightly later harvests, but it's less work.

Make sure the soil is well-prepared and has warmed up a bit. Plant seeds about ½ inch deep and thin seedlings to 18-24 inches apart. Direct sowing avoids transplant shock, but be mindful of slugs and snails that might target young seedlings.

Collard Greens need consistent moisture to thrive, especially during our humid Mid-Atlantic summers. While they're more heat-tolerant than some other brassicas, they still need regular watering to produce tender, flavorful leaves.

During the warmer months, aim to water deeply about once a week, providing around 1-1.5 inches of water. Use the "finger test" – stick your finger about 2 inches into the soil; if it feels dry, it's time to water. Water at the base of the plants to avoid wetting the leaves, which can encourage fungal diseases in our humid conditions.

Signs of underwatering include wilting leaves and slow growth. Overwatering, on the other hand, can lead to yellowing leaves and root rot. A layer of mulch around your plants helps retain moisture and suppress weeds, which is especially helpful with our even rainfall and moderate-to-hot summers.

You can expect your first harvest of Collard Greens from mid-June through late October, depending on when you planted. The leaves are ready to harvest when they're about 10-12 inches long.

Harvest the lower leaves first, leaving the top rosette to continue growing. This allows for continuous production throughout the season. The flavor of Collard Greens actually sweetens after a frost, so don't be afraid to leave them in the garden as the weather cools down.

As our first frost approaches in mid-October, you can harvest the entire plant if you'd like, or cover them for a few more weeks of harvests.

Here are some common problems you might encounter with Collard Greens in the Mid-Atlantic:

Cabbage Worms

• What it looks like: Smooth green caterpillars chewing irregular holes in leaves, dark green droppings, white butterflies nearby.
• What causes it: Larvae of white cabbage butterflies, with multiple generations possible thanks to our warm summers.
• How to fix/prevent it: Use Bt spray, which is very effective. Floating row covers prevent butterflies from laying eggs. Handpick caterpillars. Interplant with aromatic herbs.

Aphids

• What it looks like: Clusters of tiny insects (green, black, or white) on stems and leaf undersides, sticky honeydew, curled growth.
• What causes it: Rapid-reproducing sap-sucking insects, thriving in our warm weather. Ants may protect them.
• How to fix/prevent it: Strong water spray knocks them off. Encourage ladybugs. Use insecticidal soap or neem oil. Avoid excess nitrogen fertilizer.

Cabbage Loopers

• What it looks like: Similar to cabbage worms, these caterpillars are green with white stripes and move in a looping motion. They chew large holes in leaves.
• What causes it: These are the larvae of a moth. They are often found alongside cabbage worms in our Mid-Atlantic gardens.
• How to fix/prevent it: Similar to cabbage worms, use Bt spray, handpick them, and use row covers.

Downy Mildew

• What it looks like: Yellow patches on leaf tops with fuzzy gray-purple growth on undersides. Leaves brown and die from the bottom up.
• What causes it: Oomycete pathogen that spreads in cool, humid conditions, common in our region, especially during temperature swings.
• How to fix/prevent it: Remove affected leaves. Improve air circulation. Water at the base. Copper-based fungicides can help prevent it.

Mid-Atlantic Specific Challenges: Our humid summers create a favorable environment for fungal diseases like downy mildew. Keep an eye on watering practices and air circulation. Deer pressure is also a constant concern, so consider fencing or deer repellent.

Companion planting can be a great way to improve your Collard Greens' growth and deter pests here in the Mid-Atlantic.

Good companions include:

• Onion and Garlic: These alliums deter many common pests.
• Beets: They don't compete for nutrients and can improve soil health.
• Potatoes: A classic combination that doesn't hinder either crop.
• Dill: Attracts beneficial insects that prey on cabbage worms and aphids.

Avoid planting Collard Greens near:

• Strawberries: Can attract slugs and snails, which also enjoy Collard Greens.
• Tomatoes: Both are heavy feeders and can compete for nutrients in our often clay-heavy soils.