What Are the Companion Planting Benefits of Borage?

Borage (Borago officinalis) is a fast-growing annual herb with vivid blue star-shaped flowers that is widely regarded as one of the most valuable companion plants in the vegetable garden. It is easy to grow from seed, self-seeds freely once established, and offers a range of genuine benefits as a companion — from attracting pollinators and beneficial predatory insects to repelling specific pests. Its flowers are also edible and can be used as a garnish, and the leaves have culinary uses in drinks and salads.

Best companion uses for borage

Borage is particularly recommended alongside strawberries (said to improve fruit flavour and deter pests), tomatoes (where it is reputed to deter tomato hornworm), squash and courgettes (where its prolific pollinator attraction directly benefits pollination-dependent crops), and brassicas (where it attracts parasitic wasps that predate on caterpillars). In practice, its primary benefit in all of these pairings is the reliable increase in beneficial insect activity it generates throughout the garden.

Growing borage from seed

Borage is one of the easiest plants to grow from seed — direct sow outdoors from April onward, pressing seeds into the soil surface and keeping moist. Germination is rapid, and plants grow quickly to flowering size in six to eight weeks. Once established, borage self-seeds prolifically — allow a few plants to set seed and you will have volunteers appearing in the same area in subsequent years with no effort. The hairy stems and leaves can cause mild skin irritation in some people, so wear gloves when handling large quantities.

Managing borage in the garden

Borage plants are large — up to 90 cm tall and wide — so allow adequate space, particularly in a small vegetable plot. Dead-head spent flowers to prolong flowering, or allow the plant to set seed for natural regeneration. Borage is an annual so it will die after setting seed; the roots are deep and fibrous and are worth chopping up and leaving in the soil where they provide organic matter as they decompose.