Borage

Borage is an annual herb with bright blue, star-shaped flowers and wrinkled, gray-green leaves covered in bristly hairs. It is also called starflower and is native to the Mediterranean region. The plant grows about 1 foot 7 inches to 3 feet 2 inches tall (48 to 97 cm) and about 1 foot to 1 foot 4 inches (30 to 41 cm) wide. Its stems and leaves taste and smell like cucumber, and bees and other pollinators visit its flowers.

Sowing. Sow seeds outdoors as soon as the soil has warmed in spring, once frost is past. Cover seeds with ¼ to ½ inch (0.6 to 1.3 cm) of soil; another guide suggests about ½ inch (1 cm). Seeds usually come up in 7 to 14 days.

Spacing and succession sowing. Space plants about 12 inches (30 cm) apart. Sowing three times at four-week intervals stretches out the harvest.

Light and soil. Full sun is best, though light shade is fine; partial shade is also listed. The plant grows in any reasonably drained soil and does well in poor soil. Dry, sunny spots suit it best.

Transplanting. Borage dislikes being moved and develops a taproot, so direct sowing is recommended over transplanting.

Containers. It can be grown in containers, and the compact ‘Bianca’ variety with white flowers is noted as good for pots.

Watering. Water well until the seeds germinate and the plants are established, then water only when the soil is dry. The plant is listed as drought tolerant.

Feeding. Feed monthly with a balanced organic fertilizer at half the recommended rate.

Pruning and staking. Cut the plant back by half in mid-summer for new growth in fall. Trimming off older flowers keeps it blooming for many weeks. Because the stems are brittle and easily damaged by wind, staking is suggested.

Borage has no specific insect or disease problems, though powdery mildew can sometimes occur. Foliage may be damaged by slugs and leaf-mining flies, and the plant may be susceptible to powdery mildew.

Borage self-seeds readily and can spread through the garden; you can pull up the seedlings you don’t want. Expect volunteer seedlings for about two years after growing it. The stalks are prickly, so wear garden gloves when pulling plants.

Pick the blossoms as they open and use the leaves fresh, since they are seldom dried. Both the foliage and flowers can be harvested for fresh use, and the plant is rarely dried.

Borage is listed as toxic to dogs and cats, and also to horses, with signs such as vomiting, diarrhea and skin irritation. If you think a pet has eaten it, contact a veterinarian right away.

For people, use the leaves and flowers sparingly, because the plant contains natural toxins that can damage the liver and lungs; the leaves are the part listed for this concern. Only use borage seed oil that is certified as PA-free. The bristly hairs can irritate skin, so handle the plant with care during harvest.