How to grow Borage in New Zealand
Borage is an easy annual herb with bristly leaves and drooping, star-shaped sky-blue flowers that bees love, which makes it one of the most useful plants to grow near summer vegetables. Borage is a good bee plant, but it is not for eating: it is on the Food Standards Code's list of prohibited plants. Once you have it, it self-seeds and comes back year after year.
📖 Our full guide: How to Grow Borage in New Zealand
At a glance
When to sow by region
| Region | When to sow | Regional note |
|---|---|---|
| Northland | September to April | |
| Auckland | September to April | |
| Waikato & Bay of Plenty | September to April | |
| Central North Island | September to April | |
| Wellington & Lower North Island | September to April | |
| Nelson & Marlborough | September to April | |
| Canterbury | September to March | Make the last sowing in Mar so the crop is ready before winter growth stops. |
| Otago & Southland | October to March | Start spring sowings in Oct under a cloche or frost cloth, as frosts run to late October. Make the last sowing in Mar so the crop is ready before winter growth stops. |
| Central Otago | October to February | Start spring sowings in Oct under a cloche or frost cloth, as frosts run into early November. Make the last sowing in Feb so the crop is ready before winter growth stops. |
Where to plant
Sow borage in full sun in free-draining soil with a little organic matter mixed in. It is undemanding and grows fast. Plants can flop in wind, so give them a sheltered spot or a stake in exposed gardens. Plant it near crops that need bees, such as tomatoes, cucumbers, zucchini and strawberries.
- Northland, Auckland, Waikato and Bay of Plenty, the central North Island, Wellington, and Nelson and Marlborough: sow from September to April, after the frosts in spring.
- Canterbury: sow from September to March, with the last sowing in March.
- Otago and Southland: sow from October to March, starting under a cloche or frost cloth, as frosts run to late October.
- Central Otago: sow from October to February, with early sowings under cover, as frosts can run into early November.
How to plant
- Mix compost or blood and bone into a sunny spot.
- Sow seed directly where it is to grow, about 1 cm deep, and cover lightly.
- Keep the soil moist until seedlings appear, usually in 5 to 14 days.
- Thin plants to 30 to 40 cm apart.
Watering and feeding
Water regularly until plants are established, then only in dry spells. Borage needs little feeding; an occasional liquid feed encourages more leaves and flowers.
Pruning and care through the year
- Stake tall plants in windy spots.
- Leave a few plants to drop seed if you want borage to come back next year, and pull out unwanted seedlings while they are small.
- Cut spent plants and use the leaves as mulch or add them to the compost.
Cutting back and saving seed
Borage is grown for the bees, so there is nothing to harvest for the kitchen. Leave the flowers on the plant for the bees, and cut plants back or pull them out when flowering finishes. Leave a few flowers to set seed and the plant will usually come back where it grew.
Growing in pots
Borage can be grown in a deep pot, at least 25 to 30 cm, in full sun with quality potting mix. Keep the mix moist until plants establish and feed every three weeks. It gets tall, so a large pot is better.
Safety
Borage is a good bee plant, but it is not for eating: it is on the Food Standards Code's list of prohibited plants. It contains pyrrolizidine alkaloids, natural compounds that can damage the liver. Do not put borage flowers or leaves in salads, drinks, ice cubes, teas or cooking, and do not feed it to chickens or other animals.
Varieties
- Borage (blue)
- White Borage
Companion planting
Borage is grown mainly to bring bees to crops that need pollinating.
Good companions
- Strawberry Bees drawn to borage also visit the strawberry flowers.
- Tomato Brings bees and other insects into the tomato bed.
- Cucumber Cucumbers need bees to carry pollen between flowers, and borage draws them in.
- Zucchini Zucchini also needs bees to set fruit, so borage nearby helps.
Pests and diseases
Borage has very few pests.
Borage is rarely troubled by pests.
Diseases to watch for
- Powdery mildew White powdery coating on older leaves in late summer. Pull out tired plants.
Common questions
Is borage good for bees?
Yes. Its blue flowers are one of the best sources of nectar for bees in a vegetable garden, which is why it is planted near crops that need pollinating.
Can you eat borage?
No. Borage is on the Food Standards Code's list of prohibited plants, which covers Australia and New Zealand, because it contains pyrrolizidine alkaloids that can damage the liver. Grow it as a bee plant and companion flower, not as food.
Does borage come back every year?
It is an annual, but it self-seeds readily, so once it is established new plants usually come up each year.
When do I sow borage in New Zealand?
From September to March in most regions, after the spring frosts. In Otago, Southland and Central Otago, start in October under cover.
Can I transplant borage?
It is best sown directly where it is to grow. If you move self-sown seedlings, do it while they are small and water them in well.
How tall does borage grow?
Usually 60 to 100 cm. Stake it in windy gardens.
Sources we checked: Yates NZ: How to grow borage; Kings Seeds: Borage; Wikipedia: Borage; Australia New Zealand Food Standards Code, Schedule 23: Prohibited plants and fungi.