Borage in Zone 8A — Southeast

Borage is a fantastic addition to any Southeast garden. Its cucumber-flavored leaves are delicious in salads, and the vibrant blue, star-shaped flowers attract pollinators like crazy. Plus, it's just plain satisfying to grow something so beautiful and useful in our long summer.

Now, we know our hot and humid summers here in the Southeast can bring some challenges, especially with disease pressure. But with our long growing season of 245 days, and the right timing, you can easily enjoy a bountiful harvest of borage.

If you're starting borage indoors, aim to transplant seedlings outdoors in early to late March. This gives them a chance to establish before the full force of our summer heat hits.

Harden off your seedlings for about a week by gradually exposing them to outdoor conditions. Start with an hour or two of shade and increase the time and sunlight each day. Space them about 12-18 inches apart to allow for good air circulation.

Keep an eye on the weather forecast. Late frosts can still happen in early spring, so be ready to cover your young plants if needed.

Direct sowing is the easiest and most common way to grow borage, and it works great in the Southeast. You can sow seeds from mid-March through early September. Borage is so easy to direct sow, it also self-seeds readily.

Choose a spot with full sun to part shade, and make sure the soil is well-draining. Borage isn't too picky, but it will appreciate a little compost mixed in. Sow seeds about ¼ inch deep and 12-18 inches apart. Keep the soil consistently moist until the seedlings emerge, which usually takes about a week or two.

Once established, borage is pretty low-maintenance. Just be aware that it self-seeds readily, so you might find it popping up in unexpected places!

Borage needs moderate watering, especially during our hot, humid summers. While it's somewhat easy-going, it's not truly drought-tolerant, so don't let it dry out completely.

In the spring and fall, when temperatures are milder and we get more rainfall, you might only need to water once or twice a week. During the peak of summer, though, you'll likely need to water every other day, or even daily if it's exceptionally hot and dry. Stick your finger about two inches into the soil – if it feels dry, it's time to water. Aim for about an inch of water per week, either from rainfall or irrigation.

Water at the base of the plant to avoid wetting the foliage, which can encourage fungal diseases in our humid climate. Overwatering can lead to root rot, so make sure the soil is well-draining. Wilting, yellowing leaves can indicate either over or underwatering, so check the soil moisture before you react. A layer of mulch around the base of the plants helps retain moisture and suppress weeds.

You can expect your first harvest of borage flowers and leaves from early May through late November in the Southeast. That's a long harvest window! Borage is usually ready to harvest about 55 days after planting.

The star-shaped blue flowers are ready to harvest when they are fully open. Young leaves are best for eating and have a mild cucumber flavor. Harvest leaves by snipping them off near the base of the plant.

To encourage continued production, harvest flowers and leaves regularly. This prevents the plant from going to seed too quickly. As our first frost approaches in mid- November, you can let the remaining flowers go to seed if you want to encourage self-seeding for next year.

Here are the top three problems you might encounter with borage in the Southeast:

Self-Seeding Aggressively

• What it looks like: Borage seedlings popping up everywhere in your garden, even in places you didn't plant them.
• What causes it: Borage is a prolific self-seeder, and our long growing season in the Southeast gives it plenty of time to spread its seeds.
• How to fix/prevent it: Deadhead flowers before they go to seed. Pull up unwanted seedlings as they appear. Consider growing borage in containers to limit its spread.

Powdery Mildew

• What it looks like: White or grayish powdery coating on leaves, stems, and sometimes flowers. Leaves curl, yellow, and die.
• What causes it: Powdery mildew thrives in warm days, cool nights, and moderate humidity – conditions we often experience in the Southeast.
• How to fix/prevent it: Improve air circulation by spacing plants properly and pruning overcrowded growth. Remove affected leaves. Neem oil or potassium bicarbonate sprays can help. A milk spray (1 part milk to 9 parts water) is surprisingly effective.

Can Become Leggy

• What it looks like: Long, spindly stems with few leaves, especially towards the base of the plant.
• What causes it: Insufficient sunlight or overcrowding can cause borage to become leggy.
• How to fix/prevent it: Ensure your borage receives at least six hours of sunlight per day. Thin out plants to provide adequate space for growth. Prune back leggy stems to encourage bushier growth.

Southeast Specific Challenges: Our hot heat and humid humidity create ideal conditions for fungal diseases like powdery mildew. Make sure to provide good air circulation and avoid overhead watering to minimize disease pressure. Wet-summer rainfall can also contribute to fungal issues, so monitor your plants closely and take action at the first sign of trouble.

Borage is a great companion plant for many vegetables and herbs in the Southeast. It attracts beneficial insects and pollinators, and is said to deter certain pests.

Good companions:

• Tomatoes: Borage is believed to deter tomato hornworms and other tomato pests.
• Squash: Borage attracts pollinators that help with squash production.
• Strawberries: Borage is thought to improve the flavor and yield of strawberries.
• Cucumbers: Borage is a natural companion, because the leaves taste like cucumber!

Bad companions:

• Avoid planting borage near garlic or onions, as they may inhibit its growth.