Borage in Zone 6B — Mountain West

Borage is a fantastic addition to any Mountain West garden. Its vibrant blue flowers not only add beauty but also attract pollinators to your tomatoes and squash. Plus, the leaves and flowers have a refreshing cucumber-like flavor that's perfect for summer salads and drinks – a welcome treat during our brief-but-intense growing season.

Our high altitude, intense sun, and cool nights can be challenging, but Borage is adaptable. With a 163-day growing season, you have plenty of time to enjoy this herb if you time your planting right. Whether you choose to direct sow or transplant, getting Borage established is easy.

If you prefer to start Borage indoors, you can transplant seedlings outdoors from mid April through early May. Before planting, be sure to harden off your seedlings by gradually exposing them to outdoor conditions for about a week. This prevents transplant shock from our intense UV.

Space the plants 12-18 inches apart to allow for adequate air circulation. Keep an eye on the weather forecast, as late frosts are still possible. If a frost threatens, cover your young plants with row covers or blankets.

Direct sowing is the preferred method for Borage, and it's incredibly easy. Sow seeds late April through late July, once the soil has warmed up a bit. Borage germinates best when soil temperatures are consistently above 60°F.

Prepare the soil by loosening it and adding compost to improve drainage, especially in our alkaline soils. Sow seeds 1/2 inch deep and 12-18 inches apart. Keep the soil consistently moist until the seedlings emerge. Borage self-seeds readily, so be prepared for volunteer plants in subsequent years!

Borage needs moderate watering, especially in our dry Mountain West climate. While it's an easy-going plant, it's not very drought-tolerant, so consistent moisture is key, especially for young plants.

During the peak of summer, when temperatures are around 85°F and the sun is intense, water deeply about twice a week. Use the finger test: if the top two inches of soil feel dry, it's time to water. Aim for about 1 inch of water per week. Water at the base of the plant to avoid wetting the foliage, which can minimize the risk of powdery mildew, though our low humidity usually keeps it at bay.

Signs of underwatering include wilting leaves and slow growth. Overwatering can lead to yellowing leaves and root rot. A layer of organic mulch, like wood chips or straw, can help retain moisture in the soil and regulate soil temperature, which is helpful given our temperature swings.

You can expect your first Borage harvest starting mid June through mid October, about 55 days after sowing. The best time to harvest the star-shaped blue flowers is when they are fully open. The young leaves are also edible and have a mild cucumber flavor.

To harvest, simply snip off the flowers or leaves with scissors, being careful not to damage the plant. Regular harvesting encourages continued production of both flowers and leaves. As the first frost approaches in early October, harvest any remaining flowers and leaves to dry or use fresh. You can also let some of the plants go to seed to ensure you have volunteers next year.

Here are a few common problems you might encounter with Borage in the Mountain West:

Self-Seeding Aggressively

• What it looks like: Numerous Borage seedlings popping up in unexpected places throughout your garden.
• What causes it: Borage is a prolific self-seeder, and the seeds can remain viable in the soil for several years.
• How to fix/prevent it: Deadhead the flowers before they go to seed if you don't want volunteer plants. You can also pull up unwanted seedlings as they emerge.

Powdery Mildew

• What it looks like: A white or grayish powdery coating on the leaves and stems of the plant.
• What causes it: Powdery mildew is a fungal disease that thrives in warm days, cool nights, and moderate humidity. Although our humidity is generally low, microclimates in the garden can still favor its development.
• How to fix/prevent it: Improve air circulation by spacing plants properly and pruning if necessary. Remove affected leaves and dispose of them. Neem oil or potassium bicarbonate sprays can also help.

Can Become Leggy

• What it looks like: The plant stretches out, with long stems and fewer leaves, especially 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: Ensure Borage is planted in a location that receives at least 6 hours of sunlight per day. Thin out plants if they are too close together.

Mountain West Specific Challenges: While Borage is relatively easy to grow, our moderate-at-altitude heat, low humidity, and dry rainfall can still pose challenges. Monitor your plants closely for signs of stress and adjust your watering accordingly. The intense UV radiation can also scorch leaves if plants are not properly acclimated.

Borage is a great companion plant for many vegetables and herbs in the Mountain West garden. It attracts pollinators, which can increase yields for tomatoes, squash, strawberries, and cucumbers. It's said to deter tomato hornworms, which we see here sometimes. The flowers also attract beneficial insects that prey on aphids and other pests.

I don't have any bad companion plant warnings for you. Plant Borage freely throughout your garden!