Borage in Zone 8A — Pacific Northwest

Borage is a fantastic addition to any Pacific Northwest garden. With its beautiful blue, star-shaped flowers and cucumber-flavored leaves, it's a treat for both the eyes and the palate. Plus, it's a great pollinator attractant, which is always a win in our gardens.

While we might face challenges like cool springs and the occasional bout of powdery mildew, borage is pretty adaptable. Our long, mild fall also gives you plenty of time to enjoy a continuous harvest. With a growing season that stretches over 200 days, you'll find borage a rewarding plant to grow.

If you're starting your borage indoors, aim to transplant them outdoors from late March through late April. Before planting, be sure to harden off your seedlings by gradually exposing them to outdoor conditions for about a week. This helps them adjust to the cooler temperatures and brighter sunlight we often get during our wet springs.

When transplanting, space your borage plants about 12-18 inches apart to give them room to grow into their bushy habit. Keep an eye on the weather forecast, as a late frost can still happen. Protect your young transplants with row covers if needed.

Direct sowing is the easiest and most common method for growing borage in the PNW. You can direct sow from early April through late August. Borage germinates best when the soil temperature is around 60-70°F, so waiting until the soil has warmed up a bit in spring is ideal.

Prepare your garden bed by loosening the soil and removing any weeds. Sow seeds about ½ inch deep and 12-18 inches apart. Keep the soil consistently moist until the seedlings emerge, which usually takes about a week or two. Borage self-seeds readily, so be prepared to have new plants popping up in unexpected places!

Borage prefers moderate watering, which is good news for us PNW gardeners, since our dry summers mean we can usually rely on rainfall for a good portion of the season. During the dry summer months, check the soil moisture regularly. Stick your finger about 2 inches deep into the soil near the base of the plant. If it feels dry, it's time to water.

Generally, borage needs about 1 inch of water per week, either from rainfall or irrigation. Water at the base of the plant to avoid wetting the foliage, especially as the plants mature. This helps prevent fungal diseases like powdery mildew, which can be a problem in our area with its dry-summer humidity.

Signs of underwatering include wilting leaves and slow growth. Overwatering can lead to root rot, which is indicated by yellowing leaves and a generally unhealthy appearance. Applying a layer of mulch around your borage plants helps retain soil moisture and suppress weeds, reducing the need for frequent watering.

You can expect your first borage harvest around early June if you plant in early April, and you can continue harvesting through late October or early November. The best time to harvest borage flowers is when they are fully open and a vibrant blue color. The young leaves are also edible and have a refreshing cucumber-like flavor.

To harvest, simply snip off the flowers or leaves with scissors or your fingers. Regular harvesting encourages the plant to produce more flowers and leaves, extending your harvest period. As the first frost approaches in late October, harvest any remaining flowers and leaves. You can dry the flowers for later use or use the leaves fresh in salads and other dishes.

Here are some common issues you might encounter with borage in the Pacific Northwest:

Self-Seeding Aggressively

• What it looks like: Borage plants popping up in unexpected places throughout your garden.
• What causes it: Borage readily self-seeds, and our mild climate allows it to thrive and spread easily.
• How to fix/prevent it: Deadhead spent flowers before they go to seed. You can also pull out 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 flower buds. Leaves may curl, yellow, and eventually die.
• What causes it: Various fungi that thrive in our warm days, cool nights, and moderate dry-summer humidity. Dry leaf surfaces actually favor it (unlike most fungi).
• How to fix/prevent it: Improve air circulation by spacing plants adequately and pruning if needed. Remove and dispose of affected leaves. Neem oil or potassium bicarbonate sprays can help control the spread. A milk spray (1 part milk to 9 parts water) can also be surprisingly effective.

Can Become Leggy

• What it looks like: Tall, spindly plants with fewer leaves towards the base.
• What causes it: Insufficient sunlight or overcrowding can cause borage to become leggy as it reaches for more light.
• How to fix/prevent it: Plant borage in a location that receives full sun to partial shade. Thin out plants to provide adequate spacing. You can also pinch back the tips of the stems to encourage bushier growth.

Pacific Northwest Specific Challenges: Our mild summers and dry-summer humidity can create ideal conditions for powdery mildew, so good air circulation is key. While late blight is a concern for tomatoes in the region, it doesn't directly affect borage. However, keeping your garden clean and well-ventilated will help minimize the risk of any fungal diseases.

Borage is a great companion plant for several vegetables and herbs in the Pacific Northwest garden:

• Tomato: Borage attracts pollinators, which can increase tomato yields. It's also believed to deter tomato hornworms.
• Squash: The pollinators attracted by borage can also benefit squash plants, leading to better fruit set.
• Strawberry: Borage is said to improve the flavor and vigor of strawberry plants.
• Cucumber: Growing borage near cucumbers can help repel pests like cucumber beetles.

Avoid planting borage near members of the cabbage family (broccoli, kale, cabbage), as it can inhibit their growth.