Grow borage in full sun, in soil that drains. Once the roots are in, the plant can take a dry spell. Borage is Borago, an annual also sold as starflower.
Give it full sun and soil that drains
| Factor | Recommended | Avoid |
|---|---|---|
| Light | Full sun, at least six hours; light shade is fine | Do not grow it in deep shade, where stems stretch and flop |
| Water | Water while it is getting established. Later it can take a dry spell | Do not leave the roots in soggy soil |
| Soil | Well-drained loam, sand, or even poor ground | Do not plant in a wet pocket that stays soggy |
| Feed | Little or no extra fertilizer once it is in the ground | Do not keep it in rich, wet soil |
| Deer | Deer and rabbits usually leave the bristly foliage | Do not count on it if pressure is extreme |
borage wants an open, sunny bed and ground that does not stay wet. It will take light shade, and it does fine in poor soil once the taproot is down. [1] Water enough for the first weeks, then let the soil dry between waterings. Once it is established, dry ground is safer than a bog. [2] If you are sowing this spring, the seed depth and spacing are on Planting Borage. Young leaves and flowers for the kitchen are on Harvesting Borage.
- Set it in full sun. Light shade is tolerable, but the stems stay tighter and the flowers stay a deeper blue in open light.
- Water enough to get the plant established. After that, a dry spell is safer than soggy roots. [3]
- Skip heavy feeding. Rich, wet soil makes brittle stems that snap when wind hits the hollow stalks, so stake a tall plant in an open, windy bed.
How much sun does borage need?
Full sun, at least six hours. Light shade is fine. Deep shade makes weak stems that flop.
How often should I water borage?
Water while it is getting established. Later it can take a dry spell. Do not leave the roots in standing water.
Grow it in a deep pot with a drainage hole
A patio pot works when the pot is deep enough for the taproot and has a hole in the bottom. Water when the top of the mix is dry, because a pot dries faster than open ground. [4] A sunny windowsill can carry a plant indoors if you give it enough light.
- Choose a deep pot with a drainage hole. Empty the saucer so the roots do not sit in standing water.
- Use a potting mix that drains, not packed garden soil. The mix should shed water after you water.
- Water when the top of the mix is dry. Indoors, give at least five to six hours of direct sun, or about twelve hours of grow light, because the taproot still needs a deep container.
Can I grow borage in a pot?
Yes. Use a deep pot with a hole so the taproot can run, and water when the top of the mix is dry.
Cut it back by half in midsummer for a fall flush
If the plant looks tired in midsummer, cut the stems back by about half. New growth comes for a fall bloom. Do not wait until the stems are fully spent if you still want flowers later.
- In midsummer, cut the plant back by about half, above a set of leaves.
- Water once after the cut so the new shoots take hold, then return to the dry-between-waterings pattern above.
- If you do not want seedlings next spring, pick spent flower clusters before the seed drops. Unwanted seedlings pull easily.
When do I cut borage back?
In midsummer, cut the stems back by about half if you want a fall flush of growth.
Not comfrey
Borage is an annual with drooping, star-shaped blue flowers and cucumber-flavored young leaves. Comfrey is Symphytum, a hardy perennial with similar bristly leaves — see How to Grow Comfrey. Do not eat comfrey. Forget-me-not is Myosotis, a smaller blue flower — see How to Grow Forget-Me-Not. Italian bugloss is Anchusa, a perennial with upright blue spikes — see How to Grow Italian Bugloss.
Is borage the same as comfrey?
No. This plant is an annual. Comfrey is Symphytum, a hardy perennial. Do not eat comfrey.
Set it in full sun in soil that drains, water until it is established, and confirm the tag is not comfrey.
FAQ
Will borage come back next year?
Frost kills the annual. Seed that drops can sprout in spring, so a new plant may appear on its own if you leave the flower heads.
Can I plant borage next to tomatoes?
You can sow it near a vegetable bed to draw bees. Give it room so the 2 to 3 foot plant does not crowd the crop.
Is Bianca borage a different plant?
No. White compact seed strains are still the same annual with the same sun and drain. They fit a pot more easily.
Can dogs chew borage?
Keep pets from chewing the leaves. The plant can cause liver trouble if it is eaten as a regular part of the diet, so do not let dogs or cats strip the bed.
Is starflower the same as lavender star flower?
No. This herb is also sold as starflower. Lavender star flower is a different shrub.
Related guides
Recommended plants
References
- [1] NC State Extension -
https://plants.ces.ncsu.edu/plants/borago-officinalis/ - [2] Illinois Extension -
https://extension.illinois.edu/herbs/borage - [3] Missouri Botanical Garden -
https://www.missouribotanicalgarden.org/PlantFinder/PlantFinderDetails.aspx?taxonid=242362 - [4] UC Master Gardeners of Santa Clara County -
https://ucanr.edu/site/uc-master-gardeners-santa-clara-county/borage
This note is part of Borago Guides.
More first-season notes by plant are gathered in How to Grow Guides.
Updated: Reviewed by Bosquelle Editors