Borage in Zone 8B — Desert Southwest

Borage is a fantastic addition to your Desert Southwest garden, offering edible cucumber-flavored leaves and beautiful blue, star-shaped flowers that attract pollinators. Imagine adding fresh borage to your summer salads or using the flowers as a garnish – a refreshing treat in our arid climate! Plus, it's incredibly satisfying to grow something so useful and pretty in our challenging environment.

Our extreme heat, alkaline soil, and water scarcity can be tough on plants. But with borage, timing is key! Our long growing season, stretching from late February to early December, gives you ample opportunity to plant and harvest. Borage thrives when planted during the cooler parts of the year, making it a manageable and rewarding crop for Desert Southwest gardeners.

If you want a head start, you can transplant borage outdoors from mid February through mid March. Before transplanting, make sure to harden off your seedlings by gradually exposing them to outdoor conditions for about a week. This helps them adjust to our intense sunlight and dry air.

When transplanting, space your borage plants about 12-18 inches apart. This gives them enough room to bush out. Keep an eye on the weather. Even in late winter and early spring, we can experience temperature swings. Protect young transplants from unexpected dips in temperature with row covers if needed.

Direct sowing is the easiest and most common way to grow borage, and it's perfectly suited for our Desert Southwest climate. You can sow borage seeds directly into the ground from late February through late September. This gives you plenty of time to get a crop in before the first frost.

Prepare your soil by loosening it and amending with compost. Borage prefers soil temperatures between 60-70°F for optimal germination, so wait until the soil has warmed up a bit in late February or early March. Sow seeds about ½ inch deep and 12-18 inches apart. Water gently but thoroughly. Borage is known to self-seed readily, which means you might find new plants popping up on their own! This can be a blessing or a curse, depending on how much borage you want.

Borage needs moderate watering, which is especially important to get right in our dry Desert Southwest climate. While it's relatively easy-going, consistent moisture is key, especially during our hot summers and during the monsoon season.

During the spring and fall, when temperatures are milder, water deeply about once a week, providing about 1 inch of water. In the extreme heat of summer, you might need to water every other day, or even daily if the plant is wilting. Use the "finger test" – stick your finger about 2 inches deep into the soil. If it feels dry, it's time to water. 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 yellowing leaves and root rot, which is more common in poorly draining soils. Adding a layer of mulch, like wood chips or straw, around the base of the plant can help retain moisture and regulate soil temperature, which is crucial for summer survival.

You can expect your first borage harvest from late April through early December, about 55 days after planting. The best time to harvest the flowers is when they are fully open and vibrant blue. The young leaves are most tender and flavorful when they are small.

To harvest, simply snip off the flowers or leaves with scissors or your fingers. Be gentle to avoid damaging the plant. Regular harvesting encourages continued production throughout the season.

As our first frost approaches in early December, harvest any remaining flowers and leaves. While borage is frost hardy, a hard freeze can damage the plant. You can let some of the plants go to seed to ensure you have volunteers popping up next spring.

Here are the top 3 problems you might encounter growing borage in the Desert Southwest:

Self-seeding aggressively

• What it looks like: Numerous borage seedlings sprouting up in unwanted areas of your garden.
• What causes it: Borage is a prolific self-seeder, and our long growing season gives it ample time to spread its seeds.
• How to fix/prevent it: Deadhead flowers before they go to seed. Remove unwanted seedlings promptly. Consider growing borage in containers to limit its spread.

Powdery mildew

• What it looks like: White or grayish powdery coating on leaves, stems. Leaves curl, yellow, and die.
• What causes it: Fungi that thrive in warm days, cool nights, and moderate humidity. Dry leaf surfaces actually favor it.
• 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, spindly stems with fewer leaves, especially in the lower part of the plant.
• What causes it: Insufficient sunlight or overcrowding.
• How to fix/prevent it: Ensure borage receives at least 6 hours of sunlight per day. Space plants adequately (12-18 inches apart). Prune back leggy stems to encourage bushier growth.

Desert Southwest Specific Challenges: Our extreme heat and intense sunlight can stress borage plants, making them more susceptible to powdery mildew and leggy growth. The monsoon season can bring periods of high humidity, which can also exacerbate powdery mildew issues. Consistent watering and providing some afternoon shade during the hottest months can help mitigate these challenges.

Borage makes a great companion plant in the Desert Southwest garden. It attracts beneficial insects like bees and hoverflies, which are essential for pollinating many of our crops.

Good companions:

• Tomatoes: Borage is said to deter tomato hornworms.
• Squash and cucumbers: The pollinators attracted by borage help improve fruit set.
• Strawberries: Borage may help deter pests that attack strawberries.

Bad companions:

• Avoid planting borage near brassicas (cabbage, broccoli, kale). It can sometimes hinder their growth.