Borage

About Borage

Borage is a bristly annual with star-shaped blue flowers that bees love. It reseeds itself readily, and its young leaves taste like cucumber, though they should be eaten only sparingly.

Grown as an annual in every zone (NC State lists 2-11); self-sown seedlings return year after year.

When to plant

Timing is counted from your average last spring frost (and first fall frost). Sow & Tell works out the actual dates for your ZIP code.

• Sow seeds outdoors: up to 2 weeks after the last frost

Sow directly in the garden after frost is past; it is difficult to transplant. Space plants 12 inches apart in rows 18 inches apart.

Soil

Adapts to clay, loam or sandy soil and a wide pH range; drought tolerant.

Plant in a sunny spot in well-drained soil; borage does well even in poor or dry soil once established.

Feeding

Very fertile soil or heavy feeding gives lots of leafy growth with less flavor and can encourage root and stem rot.

Harvest

Pick young leaves and flowers as needed; wear gloves, since the stiff hairs can irritate skin.

Varieties (3)

Only 3 named borage selections are documented in extension sources; most gardeners grow the plain blue-flowered species.

Diseases and problems

Powdery mildew

In the kitchen

Flowers garnish drinks and desserts, and young leaves add a cucumber flavor to salads and soups, in small amounts only.

Keeping it: Pick edible flowers the day you use them; if you must hold them, keep them in a plastic bag in the fridge for a day or so.

Safety: Borage contains pyrrolizidine alkaloids that can damage the liver (and lungs) and may cause cancer, so eat leaves only sparingly and use only certified PA-free seed oil. Avoid it in pregnancy, and it may raise bleeding risk with blood thinners (MSKCC, NC State).

Pets: Toxic to dogs, cats and horses (ASPCA): can cause vomiting, diarrhea and skin irritation