Borage in Zone 3A — Mountain West

Borage is a fantastic addition to any high-altitude garden. Its beautiful blue, star-shaped flowers attract pollinators to your vegetable patch, and the cucumber-flavored leaves and edible flowers add a unique touch to salads and drinks. Plus, it's just plain satisfying to grow something so pretty and useful in our Mountain gardens.

Our short growing season and intense sun can be a challenge, but borage is quick to mature, making it a perfect fit for our 96-day window. With a little attention to watering, you can enjoy a bountiful harvest of both leaves and flowers.

You can transplant borage outdoors from mid May through mid June. Remember to harden off your seedlings for about a week before planting. Gradually expose them to the intense sun and cooler nighttime temperatures of our Mountain climate.

Space your plants 12-18 inches apart to allow for good air circulation. Keep an eye on the weather forecast around transplant time. Late frosts and unexpected hail are always a possibility in the Mountains, so be ready to cover your young plants if needed.

Direct sowing is the easiest and most common way to grow borage here. Wait until early to late June, when the soil has warmed up a bit. Borage needs soil temperatures above 60°F to germinate well.

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

Borage needs moderate watering, especially during our dry Mountain summers. While it's a pretty easy-going plant, it's not particularly drought-tolerant, so consistent moisture is key.

During the peak of summer, when temperatures are around 85°F, aim to give your borage plants about 1 inch of water per week. Use 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 getting the leaves wet, which can encourage fungal problems, even in our low-humidity environment.

Signs of underwatering include wilting leaves and stunted growth. Overwatering can lead to yellowing leaves and root rot. A layer of mulch around your plants will help retain moisture and keep the soil cooler during those intense sunny days we get here.

You can expect your first borage harvest from late July through mid September, about 55 days after sowing. The star-shaped blue flowers are ready to harvest when they are fully open. The young leaves are also edible and taste like cucumber.

To harvest the flowers, simply snip them off the stem. For the leaves, harvest the younger ones as needed. Regular harvesting encourages continued production. As the first frost approaches in early September, harvest any remaining leaves and flowers. You can let some flowers go to seed if you want borage to self-sow for next year.

Here are the most common problems you might encounter growing borage in the Mountain West:

Self-Seeding Aggressively

• What it looks like: Borage plants popping up in unexpected places in your garden, even the following year.
• What causes it: Borage is a prolific self-seeder. Seeds drop to the ground and germinate readily, especially with our dry climate allowing seeds to persist.
• How to fix/prevent it: Deadhead flowers before they go to seed. Remove unwanted seedlings as soon as you see them. Consider growing borage in a container to limit its spread.

Powdery Mildew

• What it looks like: White or grayish powdery coating on leaves and stems. Leaves might curl, yellow, and die.
• What causes it: Fungi that thrive in warm days and cool nights, which we often experience. Dry leaf surfaces favor it, despite the low humidity.
• How to fix/prevent it: Improve air circulation by spacing plants adequately. Remove affected leaves promptly. Neem oil or potassium bicarbonate sprays can help. A milk spray (1 part milk to 9 parts water) is another effective option.

Can Become Leggy

• What it looks like: Tall, spindly plants with fewer leaves and flowers, often flopping over.
• What causes it: Insufficient sunlight or overcrowding. Plants stretch towards the light, resulting in weak stems.
• How to fix/prevent it: Plant in full sun to part shade. Ensure adequate spacing between plants (12-18 inches). Prune back leggy stems to encourage bushier growth.

Mountain West Specific Challenges: Our intense sun can sometimes scorch the leaves, especially if the plants are not getting enough water. The alkaline soil can also affect nutrient uptake, so amend your soil with compost before planting. Hail storms can damage leaves and stems, so consider using row covers or netting for protection during periods of severe weather.

Borage makes a great companion plant for several vegetables in our Mountain gardens. It attracts pollinators, which benefit tomatoes, squash, strawberries, and cucumbers. Borage is thought to deter tomato hornworms and squash bugs, making it a valuable addition to your garden. I haven't found any plants that particularly dislike growing near borage, so feel free to experiment.