Borage in Zone 7B — Southeast

Borage is a fantastic addition to any Zone 7B garden. Its cucumber-flavored leaves and beautiful blue, star-shaped flowers are edible, attracting pollinators and adding a unique touch to salads and drinks. Plus, it's a rewarding plant to grow, especially with our long summer days and reliable rainfall.

Our hot and humid Southeast summers can present challenges like powdery mildew, but with a little attention to timing and spacing, you can easily enjoy a bountiful harvest of borage. With our long growing season—around 235 days—you'll have plenty of time to enjoy this versatile herb.

You can transplant borage outdoors from early March through early April. Before planting, it's important to harden off your seedlings by gradually exposing them to outdoor conditions for about a week. This helps them adjust to the sun and temperature changes.

When transplanting, space the plants 12-18 inches apart. Keep an eye on the weather, as late cold snaps can still occur during this time. If a frost is predicted, cover your young plants to protect them.

Direct sowing is the preferred method for borage, and it's incredibly easy. You can sow seeds directly into the garden from mid March through early September. Borage germinates best when the soil temperature is around 60-70°F, so waiting until the soil has warmed up a bit in the spring is ideal.

Prepare your soil by loosening it and adding some compost. Sow the seeds about ½ inch deep and 12-18 inches apart. Keep the soil consistently moist until the seedlings emerge. Borage is known to self-seed readily, so be prepared to have it pop up in unexpected places!

Borage needs moderate watering to thrive in our Southeast gardens. While it's a fairly easy-going plant, consistent moisture is key, especially during our hot summers. Remember, even though we get reliable rainfall, afternoon thunderstorms aren't always enough to deeply water your plants.

During the spring and fall, when temperatures are milder, aim to water your borage about once a week, providing about 1 inch of water. In the heat of summer, you may need to water more frequently, especially if you notice the leaves wilting. A good way to check is the "finger test": 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 foliage, which can encourage fungal diseases in our humid climate. Signs of underwatering include wilting leaves and stunted growth. Overwatering can lead to root rot, so make sure your soil is well-draining. Applying a layer of mulch around your borage plants can help retain moisture and suppress weeds, which is especially helpful in our long, hot summer.

You can expect your first borage harvest from mid May through mid November, about 55 days after planting. Look for the star-shaped blue flowers to be fully open; these are a great indicator that the plant is ready for harvesting. The young leaves are also edible and have a refreshing cucumber flavor.

To harvest, gently snip off the flowers or leaves with scissors or pruners. Avoid pulling or tearing the plant, as this can damage it. Regular harvesting encourages continued production, so don't be shy about using your borage.

As our first frost approaches in early November, you can still harvest any remaining flowers and leaves. Consider letting some of the plants go to seed if you want them to self-sow for next year.

Borage is generally easy to grow, but here are a few common problems to watch out for 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 the seeds are easily spread by wind and animals.
• How to fix/prevent it: Deadhead the flowers before they go to seed. If you want to save some seeds, collect them carefully and store them in a sealed container. Remove unwanted seedlings as soon as you see them.

Powdery mildew

• What it looks like: White or grayish powdery coating on leaves, stems, and sometimes flower buds. Leaves may curl, yellow, and eventually die.
• What causes it: Various fungi that thrive in warm days, cool nights, and moderate humidity. Dry leaf surfaces actually favor it, which can be a problem even with our wet-summer rainfall patterns.
• How to fix/prevent it: Improve air circulation by spacing plants properly and pruning overcrowded areas. Remove affected leaves promptly. Neem oil or potassium bicarbonate sprays can help control the spread. A milk spray (1 part milk to 9 parts water) is also 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 light.
• How to fix/prevent it: Ensure your borage plants receive at least 6 hours of sunlight per day. If they're in a shady spot, consider moving them or providing supplemental light. Pruning can also help encourage bushier growth.

Southeast Specific Challenges: Our hot, humid summers and frequent rainfall create ideal conditions for fungal diseases like powdery mildew. Be vigilant about providing good air circulation and avoiding overhead watering to minimize disease pressure.

Borage is a great companion plant for several vegetables and herbs in your Southeast garden. It attracts pollinators, which benefits tomatoes, squash, strawberries, and cucumbers. It's said to deter tomato hornworms.

I haven't found any definitive bad companions for borage, but keep in mind its tendency to self-seed. Give it enough space so it doesn't overwhelm smaller, less vigorous plants.