How to grow basil in Australia 🌿

Basil needs warm soil (consistently 18°C+) and warm air. It's killed by frost and slow in cool weather. Most Australian gardeners get it wrong by planting too early — patience pays.

Basil can be grown from seed or seedlings. Seedlings are the easier choice for most home gardeners — they give you a 4-week head start.

Spacing: 25–30cm between plants. Crowding reduces airflow and increases disease risk.

Depth: Sow seeds 5mm deep. Seedlings go in at the same depth they grew in the pot.

Soil: Rich, well-drained soil with plenty of compost. Slightly acidic to neutral pH.

Pinching: Pinch out the central growing tip when the plant is 15–20cm tall. This encourages bushy growth and delays flowering. Continue pinching flower buds throughout the season — once basil flowers, leaf production slows dramatically and the leaf flavour declines.

Basil is one of the most pot-friendly herbs — possibly the easiest herb for balcony and kitchen window gardens.

In-ground works well, especially planted alongside tomatoes where the two share conditions and pests are slightly reduced.

Raised beds suit basil — improved drainage and warmer soil help in cool climates.

Pots are arguably the ideal home for basil. A 20–25cm pot supports a single plant for the full season. Wider pots can hold 2–3 plants for a continuous harvest. The advantage of pots is mobility — bring basil indoors as the weather cools to extend the productive period, or move pots to follow the sun. Use quality potting mix; cheap mix dries fast and produces stressed, bitter leaves.

Full sun — 6 to 8 hours daily. In tropical and semi-arid climates, afternoon shade through summer reduces wilt and bolt risk.

Water consistently. Basil wilts dramatically when dry but recovers fast once watered. Mulch helps in hot climates. Water in the morning rather than evening so leaves dry before night.

Pick leaves from the top of the plant rather than the bottom. Cut just above a pair of leaves and the plant branches at that point, producing two new shoots where there was one. Picking like this turns a leggy single-stem plant into a bushy productive one.

Harvest regularly — at least weekly during peak season — to keep new leaves coming. A plant that isn't picked sets seed and slows leaf production.

Best used fresh. Basil doesn't dry well (flavour disappears) but freezes well in oil (blend leaves with olive oil, freeze in ice cube trays) or as part of pesto.

Bolting to flower is the most common basil issue. Caused by heat stress, water stress, or simply plant maturity. Pinch flowers as they appear to extend leaf production. Once a plant is determinedly flowering, harvest everything remaining and start a new planting.

Downy mildew appears as yellow patches on upper leaves with grey mould on the undersides. Most common in humid coastal climates. Improve airflow with proper spacing; water at soil level only; remove affected leaves promptly.

Slugs and snails on young plants. Beer traps or iron-based bait.

Aphids on tender new growth. Strong water spray or insecticidal soap.

Plant near: Tomato (the classic combination — same conditions, complementary in the kitchen), capsicum, eggplant, asparagus, marigold.

Keep away from: Rue and sage (allelopathic interactions reduce growth).

Sweet Basil (Genovese) — The classic Italian basil. Large, soft leaves with strong sweet flavour. The standard for pesto and Italian cooking. Most reliable variety across Australian climates.

Thai Basil — Smaller leaves, purple stems, slight anise flavour. Used in Southeast Asian cooking. More heat-tolerant than Genovese; suits warm climates particularly well.

Lemon Basil — Citrus-scented variety. Excellent in fish dishes and salads. Heritage seed suppliers.

Purple Basil (Dark Opal) — Decorative as well as edible. Deep purple leaves. Slightly milder flavour. Beautiful in salads.

Greek Basil (Bush Basil) — Compact, small-leaved variety forming a tight ball shape. Excellent for pots. Strong flavour despite tiny leaves.

Cinnamon Basil — Distinct cinnamon-clove scent. Heritage variety, available from speciality suppliers.