Borage is an annual herb with cucumber-flavored leaves and star-shaped edible flowers. University of Illinois Extension lists plants at about 2 to 3 feet tall, preferring full sun and doing well on dry soils once established. The harsh hairs can irritate some people's skin.
Borage at a glance
| Type | Herb |
|---|---|
| Season | Warm-season |
| Sun | Full sun |
| Plant spacing | 12 in |
| Row spacing | 18 in |
| Per square foot | 1 |
| Seed depth | ¼ in |
| Days to maturity | Sow every 4 weeks for tender leaves |
| How to start | Start seed indoors, or sow directly in the garden after frost is past. |
| Water | 0.5 in per week |
These are the same numbers our plant spacing, square foot and harvest date calculators use. See every crop in the plant database.
When to plant borage
Start seed indoors, or sow directly in the garden after frost is past. For a steady supply of culinary foliage, sow successively every four weeks. Use the frost dates by ZIP code and planting calendar.
How to plant borage
- Choose full sun.
- Skip heavy watering. It does well on dry soils once established; see the garden watering calculator.
- Stake the plants. Illinois suggests staking because the plant is brittle and easily damaged by wind.
- Check spacing with the plant spacing calculator.
Caring for borage
Wear gloves when handling the plant, since the harsh hairs can irritate skin.
Companion plants
| Grow nearby | Tomatoes, squash and strawberries |
|---|---|
| Keep apart | Windy, exposed sites without support |
Borage is brittle, so shelter from wind helps. Check other pairings with the companion plant finder.
Common problems
| Problem | What you see | What to do |
|---|---|---|
| Skin irritation | Itchy skin after handling | The harsh hairs can irritate some people's skin; wear gloves. |
| Wind damage | Broken, floppy stems | Stake the plants; they are brittle. |
Not sure what you are looking at? The plant problem identifier ranks likely causes from the symptoms you see.
When and how to harvest
Both foliage and flowers can be harvested for fresh use; borage is rarely dried. Leaves have a cucumber-like flavor for salads, soups, stews and beverages. Flowers work as an edible garnish or in desserts and drinks.
Plan your borage
- Plant spacing calculator: how many plants fit your bed
- Planting calendar: sowing and transplant dates for your frost dates
- Frost dates by ZIP code: your last spring and first fall frost
- Harvest date calculator: when your crop will be ready
Frequently asked questions
How far apart should I plant borage plants?
Space borage plants 12 inches apart in rows 18 inches apart. In a square foot garden, plant 1 per square foot.
How deep do I plant borage seeds?
Sow borage seed after frost, or start indoors, in full sun.
How long do borage plants take to grow?
Sow successively every 4 weeks for a steady supply of tender leaves.
How much water do borage plants need?
About 0.5 inches of water a week, from rain and watering combined. Once established it does well on dry soil.
Is borage an annual?
Yes, University of Illinois Extension lists it as an annual.
What does borage taste like?
The leaves have a cucumber-like flavor.
Can I eat borage flowers?
Yes, as a garnish or in desserts and drinks.