How to grow borage in Australia

Borage is a hardy annual best direct-sown where it's to grow, from spring through summer (and autumn in frost-free zones). It dislikes transplanting, so sow in place.

Direct-sow seed where the plants are to grow — borage has a taproot and resents being moved.

Spacing: About 40cm apart; plants get bushy and can reach 60–90cm.

Depth: Sow about 1cm deep and keep moist until germination (usually fast in warm soil).

Soil: Tolerant of poor soil; any reasonable, free-draining soil is fine. No special pH needs and little feeding required.

Self-seeding: Let a few flowers set seed and you'll have volunteer plants for years — pull out unwanted seedlings while small.

In-ground scattered among fruiting crops is the classic, beneficial use — borage earns its place by drawing pollinators.

Pots (medium+) work for a single plant on a balcony, though borage's size and taproot mean it's happiest in the ground.

Raised beds suit it well; just be aware it will self-seed into neighbouring spaces.

Borage tolerates part shade but flowers most profusely in full sun.

Water moderately — established plants are fairly drought-tolerant, but consistent moisture keeps them lush and flowering. It's an undemanding plant overall; overly rich soil produces leaf at the expense of flowers.

Pick the edible blue flowers as they open — they have a mild cucumber flavour and make a beautiful garnish for salads, drinks, and frozen in ice cubes. Young leaves are also edible (cucumber-like) but become bristly with age, so use them small.

Harvest flowers regularly to encourage more, and let the last flush set seed if you want self-sown plants next season. Note the leaves contain pyrrolizidine alkaloids, so eat them only occasionally and in small amounts; the flowers are the safe, everyday pick.

Powdery mildew late in the season or in crowded plantings — improve spacing and airflow; it's usually a late-life cosmetic issue.

Aphids can cluster on new growth — they also attract the beneficial insects borage is famous for, so often resolve themselves; hose off if heavy.

Flopping — tall plants can sprawl, especially in rich soil or shade; give them sun and space, or support loosely.

Over-enthusiastic self-seeding — the main "problem"; pull unwanted seedlings while young.

Borage is one of the great companion plants. Its flowers draw bees and hoverflies that boost pollination and fruit set, so it's ideal planted near tomato, strawberry, blueberry, and the citrus and passionfruit it supports here. It's traditionally credited with improving the flavour and vigour of nearby tomatoes and strawberries.

Because it self-seeds and grows large, give it room at the edges of beds rather than crowding smaller crops.

Common Blue Borage — the classic vivid-blue starflower; the best bee attractor and the standard choice.

Alba (white flower) — a white-flowered form with the same habit and uses; pretty in mixed plantings.

Creeping Borage — a lower, spreading perennial relative grown more as a groundcover than the edible annual; useful for filling space but less productive of the familiar edible flowers.