Borage
Starflower, Bee Bush, Cool-tankard, Beebread, Beeplant, Borage, Boražina
Annual herb with stunning blue star-shaped edible flowers. Excellent companion plant — deters tomato hornworm and cabbage worms, attracts pollinators throughout the season. Direct sow after last frost; taproot makes it difficult to transplant. Self-seeds prolifically — pull unwanted seedlings early. Both leaves (young ones) and flowers are edible with a mild cucumber flavor. Thrives in poor soils.
- Germination
- 7–14 days
- Soil temperature
- 18–24 °C
- Harvest after sowing
- 50–70 days
- Spacing
- 30–45 cm
When to plant borage
Sow outdoors from 1 week before to 2 weeks after your last spring frost.
Dashed line: typical last spring frost in zone 7 (Apr 5). Zone dates are averages; most of the UK is zone 8–9, central Europe 6–7 and the Baltics and Scandinavia 4–6. In the app, Tomatograph uses your garden's own frost dates.
How to grow borage
- 1
Sow direct
Sow 1 cm deep around the last frost, where it is to grow; the taproot makes it hard to move. Thin to about 45 cm apart.
- 2
Let it grow
Borage thrives in poor soil and needs little care.
- 3
Use as a companion
The blue flowers attract bees all season and help pollinate nearby tomatoes, squash and strawberries.
- 4
Harvest
Pick young leaves and flowers from about 50 days; both taste mildly of cucumber. It self-seeds freely, so pull unwanted seedlings early.
Growing conditions
Light
Full sun
Water
Low water
Temperature
4–30 °C
Frost tolerance
Frost-sensitive — protect below 0 °C
Days to maturity
50–70 days
Ideal soil pH
6.5–7
How Tomatograph watches your borage
Tomatograph checks your local forecast every morning and only speaks up when one of these applies to your garden.
- Forecast of 2 °C or lowerFrost alert the evening before: cover plants with fleece or bring pots inside.
- 3 days at 35 °C or aboveHeat-wave alert while plants are flowering or fruiting: shade and water early.
- Humidity above 80% for 48 hoursCheck for powdery mildew, which thrives in those conditions.
- Within a week of maturityHarvest-window reminder based on when you planted.
Borage questions
- When should I plant borage?
- Sow outdoors from 1 week before to 2 weeks after your last spring frost.
- How long do borage seeds take to germinate?
- Usually 7–14 days at a soil temperature of 18–24 °C.
- How long until I can harvest borage?
- About 50–70 days after sowing, depending on variety and weather.
- How far apart should I plant borage?
- Allow 30–45 cm between plants.
- What grows well with borage?
- Good neighbours include tomato, strawberry, squash, cucumber.
Growing guide written by Tomatograph. Planting figures from openplantdb (CC0 1.0). Zone frost dates are averages from openplantdb (CC0 1.0).