How to grow Borage in Australia
Borage (Borago officinalis) is a tough, bristly annual herb with star-shaped, sky-blue flowers that bees love. It is one of the best plants for bringing pollinators and helpful insects into the vegie patch, it self-seeds freely, and its flowers make a pretty garnish. Sow it once and it tends to come back year after year.
📖 Our full guide: How to Grow Borage in Australia
At a glance
When to sow by region
| Region | When to sow | Regional note |
|---|---|---|
| South East Queensland | March to September | |
| Northern Rivers NSW | March to September | |
| Sydney & Coastal NSW | March to September | |
| Melbourne & Victoria | March to September | Frost-tolerant; sow Mar to Sep. Melbourne cool season ideal. Reseed autumn. |
| Adelaide & SA | March to September | |
| Perth & WA | March to September | |
| Tasmania | September to November | Sow Sep to Nov. Self-seeds freely. Bees love it. |
| Canberra & ACT | March to September | Borage is cold-tolerant annual; sow spring-autumn; edible flowers; reseeds readily; loses vigor in hot summer. |
| North Queensland | May to September | Dry season May to Sep. Borage annual; thrives in dry season. |
| Darwin & Top End | May to September | Dry season May to Sep. Borage annual; thrives in dry season. |
Where to plant
Borage grows in full sun in almost any well-drained soil, and prefers soil with a little compost. It is drought tolerant once established and needs no fertiliser; rich soil gives big leafy plants with fewer flowers. It has a long taproot and dislikes being moved, so sow it where it is to grow.
Plants grow into a large, bristly bush, so give them room at the end of a bed or among fruit and vegetables that need pollinating.
- Melbourne, Canberra, Sydney, Adelaide and Perth: sow from autumn through winter to early spring. Plants lose vigour in hot summers.
- Hobart: sow from September to November.
- South East Queensland and the Northern Rivers: sow from autumn to early spring.
- North Queensland and Darwin: sow in the dry season, May to September.
How to plant
- Sow seed directly into the garden about 1 cm deep.
- Keep the soil moist until seedlings appear, usually within two weeks.
- Thin seedlings to about 40 cm apart.
- After that, water only in dry spells.
Watering and feeding
Water young plants until they are established, then borage copes well with dry conditions. It needs no feeding in most soils, and heavy feeding gives leaves at the expense of flowers.
Pruning and care through the year
- Stake plants lightly in windy spots; the hollow stems are brittle.
- Borage self-sows prolifically. Leave a few plants to seed if you want it back, and pull unwanted seedlings while they are small.
- Wear gloves when handling older plants, as the bristly leaves and stems can irritate skin.
Picking flowers and leaves
Pick flowers when they are fully open and bright blue, ideally in the morning. Pull the flower gently away from its hairy green base. Pick young leaves sparingly; older leaves become unpleasantly prickly.
Use flowers on the day you pick them, or freeze them in ice cubes.
Growing in pots
Borage can grow in a pot at least 25 cm wide and deep, though it gets tall and floppy. Use ordinary potting mix and do not feed.
Using it
- The flowers have a mild, cucumber-like taste. Use them to decorate salads, cakes and drinks, or freeze them in ice cubes.
- Young leaves also taste of cucumber, but borage contains small amounts of pyrrolizidine alkaloids, natural compounds that can damage the liver if eaten in large amounts over time. Enjoy the flowers and the occasional young leaf as a garnish rather than eating the leaves regularly. NC State Extension lists the plant as toxic to cats, dogs and horses.
Companion planting
Borage is grown in the vegie patch mainly for its flowers, which bring in bees to pollinate fruiting crops, and hoverflies whose larvae eat aphids.
Good companions
- Strawberry Draws bees to pollinate the flowers, which helps fruit set.
- Tomato Its blue flowers bring in bees and hoverflies.
- Cucumber Brings in bees to pollinate the separate male and female flowers.
- Zucchini Brings in bees for better fruit set.
Pests and diseases
Borage is rarely troubled by pests. Powdery mildew is common on old plants late in the season.
Borage is rarely troubled by pests.
Diseases to watch for
- Powdery mildew White, powdery patches on older leaves, especially as plants age or in dry spells. Pull out old plants; self-sown seedlings will replace them.
Common questions
Is borage safe to eat?
The flowers are widely used as a garnish. Borage contains small amounts of pyrrolizidine alkaloids, which can damage the liver if eaten in large amounts over a long time, so treat the leaves and flowers as an occasional garnish rather than a regular vegetable. The plant is also listed as toxic to pets and livestock if eaten in quantity.
Does borage come back every year?
Borage is an annual, but it self-seeds so freely that new plants usually appear each year where it grew before.
Why is borage good in the vegie garden?
Its flowers are a magnet for bees and helpful insects such as hoverflies. Bees improve pollination of strawberries, tomatoes, cucumbers and zucchini, and hoverfly larvae eat aphids.
Can you transplant borage?
It is best sown where it is to grow. Borage has a long taproot and resents being moved, so transplant only small seedlings, if at all.
What does borage taste like?
Both the flowers and young leaves have a mild, fresh taste similar to cucumber.
When should I sow borage?
In most of southern Australia, sow from autumn to spring. In the tropics, sow in the dry season. Pick your region at the top of the page for the months.
Sources we checked: ABC Organic Gardener: Grow borage; NC State Extension Gardener Plant Toolbox: Borago officinalis; FSANZ: Pyrrolizidine alkaloids in foods; Molecules (2019): review of pyrrolizidine alkaloids in plants.