Borage in Zone 7A — Desert Southwest

Borage is a fantastic addition to any Desert Southwest garden. Its beautiful blue, star-shaped flowers are edible and attract pollinators, plus the young leaves have a refreshing cucumber flavor perfect for our hot climate. Growing your own means fresh ingredients right outside your door, and the satisfaction of nurturing something beautiful and useful in our challenging environment.

Desert gardening definitely has its hurdles, from extreme heat to alkaline soil. But with our long 230-day growing season and some smart timing, you can absolutely enjoy a thriving Borage patch. We'll cover the best ways to get this rewarding plant established and flourishing in your garden.

If you're starting Borage from transplants, aim to get them in the ground from mid-March through early April. This gives them a chance to establish before the real heat kicks in.

Before planting, harden off your seedlings. Give them about a week of gradual exposure to the outdoors, increasing their time in direct sunlight each day. Space them 12-18 inches apart to allow for good air circulation.

Keep an eye on the weather during this time. We can still get some temperature swings in early spring, so protect your young plants with row covers if a late frost threatens.

Direct sowing is the preferred method for Borage, and it's super easy. You can sow seeds directly into your garden beds from late March through early September, taking advantage of both our growing seasons. Borage is also known to self-seed readily, so prepare for volunteers!

Choose a spot with full sun to partial shade and prepare the soil by loosening it and adding some compost. Borage isn't too picky, but good drainage is always important. Sow seeds about 1/2 inch deep and 12-18 inches apart. Keep the soil consistently moist until germination, which should occur within a week or two.

Once established, Borage is pretty low-maintenance. Just be sure to thin seedlings as needed to give each plant enough room to thrive.

In our Desert Southwest climate, watering is key to success with Borage. While it's relatively easy-going, consistent moisture is important, especially during our extreme summer heat.

During the spring and fall growing seasons, aim to water deeply about 2-3 times per week, providing about 1 inch of water each time. In the peak of summer, you'll likely need to increase that to every other day, or even daily during the hottest stretches. The "finger test" is your best guide: stick your finger about 2 inches into the soil. If it feels dry, it's time to water. During the monsoon season, adjust your watering based on rainfall.

Water at the base of the plant to avoid wetting the foliage, which can encourage powdery mildew. Signs of underwatering include wilting leaves and stunted growth. Overwatering can lead to root rot, so watch out for yellowing leaves. A layer of mulch around your Borage plants will help retain moisture and keep the soil cooler.

You can expect your first Borage harvest starting around mid-May and continuing through mid-November if you keep up with deadheading. Borage is ready to harvest about 55 days after sowing.

The star-shaped blue flowers are ready to pick when they are fully open. The young leaves are best harvested when they are small and tender. Snip off the flowers or leaves with scissors or your fingers, taking care not to damage the rest of the plant.

Regular harvesting encourages continued production. As the first frost approaches in early November, harvest any remaining flowers and leaves. You can also let some flowers go to seed if you want Borage to self-sow for the following season.

Here are some common problems you might encounter with Borage in the Desert Southwest:

Self-Seeding Aggressively

• What it looks like: Borage seedlings popping up everywhere in your garden where you didn't plant them.
• What causes it: Borage is a prolific self-seeder, and in our long growing season, seeds can mature and sprout quickly.
• How to fix/prevent it: Deadhead flowers regularly before they go to seed. If you want some self-seeding, allow a few flowers to mature, but remove the rest. Pull up unwanted seedlings as soon as you see them.

Powdery Mildew

• What it looks like: White or grayish powdery coating on leaves, stems. Leaves curl, yellow, and die.
• What causes it: Various fungi that thrive in warm days, cool nights, and moderate humidity. Dry leaf surfaces actually favor it. Even though we're arid, our monsoon season can bring enough humidity for powdery mildew to take hold.
• How to fix/prevent it: Improve air circulation through spacing and pruning. Remove affected leaves. Neem oil or potassium bicarbonate sprays help. Milk spray (1 part milk to 9 parts water) is surprisingly effective.

Can Become Leggy

• What it looks like: Long, bare stems with leaves concentrated at the top.
• What causes it: Insufficient sunlight or overly rich soil can cause Borage to stretch and become leggy.
• How to fix/prevent it: Ensure your Borage plants receive at least 6 hours of sunlight per day. Avoid over-fertilizing. Prune back leggy stems to encourage bushier growth.

Desert Southwest Specific Challenges: Our extreme heat can stress Borage, making it more susceptible to powdery mildew and causing it to bolt (go to seed prematurely). The monsoon season can also create favorable conditions for fungal diseases. Be sure to provide adequate shade during the hottest part of the day and monitor your plants closely for any signs of stress.

Borage is a great companion plant for many garden vegetables in the Desert Southwest. It attracts pollinators, which benefits tomatoes, squash, and cucumbers. It's also said to deter tomato hornworms.

Borage is known to improve the growth and flavor of strawberries. The reason these are good pairings is that they all benefit from the increased pollinator activity from the Borage flowers.

I wouldn't recommend planting Borage near fennel, as it can inhibit its growth. Otherwise, Borage is a pretty easy-going companion in the garden.