Ocimum basilicum var. purpurascens

Sowing and care tips for purple basil

Ocimum basilicum var. purpurascens seeds appreciate warmth and bright light. Start indoors before last frost in a free-draining, fertile mix; keep 18–24°C for fast germination. Transplant only after all danger of frost, when nights are warm, or direct sow into warm, well-drained soil in full sun. Space plants to allow good air flow and branching, following packet guidance for your selection. Water regularly to keep soil evenly moist but never waterlogged; feed lightly once established. Pinch early and harvest tips to encourage a compact, medium-height habit and delay flowering. Remove weeds and mulch lightly to retain warmth. In mild climates, autumn sowing may be possible.

• Leaves are edible; harvest lightly and often to encourage fresh shoots.
• Deep purple foliage offers ornamental interest; provide full sun for richest colour.
• Small blooms can attract pollinators; pinch early flower spikes to prolong leafy growth.
• Suitable for containers; use a warm, free-draining, fertile mix in a sunlit, sheltered spot.

How do I grow purple basil (Ocimum basilicum var. purpurascens) from seed?

Sow seeds indoors 4–6 weeks before the last frost in trays or small pots of fine, well-drained seed compost. Press seeds onto the surface and barely cover (1–2 mm), as light aids germination. Maintain even moisture and warmth; a soil temperature of 20–25°C speeds germination (typically 5–14 days). Provide bright light to prevent leggy growth. Prick out to individual cells once true leaves appear. Harden off gradually, then transplant outside when nights are reliably warm. Alternatively, direct sow after last frost into warm, friable soil and thin to strong, well-spaced plants.

When should I sow and transplant purple basil relative to the last frost?

Start indoors before the last frost, then transplant only after all danger of frost has passed and night temperatures stay consistently mild. Basil is cold-sensitive; growth stalls if nights are chilly. Direct sowing is suitable after the last frost once soil is warm to the touch—aim for soil above about 15°C for steady emergence. In mild climates, a late spring sowing establishes fastest; in areas with very warm summers, successive sowings can extend the season. Always harden off indoor-raised seedlings for 7–10 days before planting out.

What sun and soil conditions does purple basil need, and what’s the best container mix?

Provide full sun—ideally 6–8 hours of direct light daily; in areas with intense midsummer heat, very light afternoon shade can reduce leaf scorch. Grow in warm, well-drained, fertile soil enriched with mature compost and avoid waterlogging. For containers, use a high-quality, peat-free, free-draining mix with added perlite or grit for aeration. A pot 15–25 cm wide (larger for multiple plants) with good drainage suits single plants; fabric or terracotta containers help prevent soggy roots. Keep soil evenly moist but not saturated, and feed lightly with a balanced, organic fertiliser during active growth.

How far apart should I space purple basil plants, and how tall will they get?

Purple basil is generally compact to medium in habit, typically maturing 30–60 cm tall depending on variety, light, and nutrition. Space plants to encourage airflow and branching: 20–30 cm between plants in the row and 30–45 cm between rows is a common guide. In containers, allow similar spacing or grow one plant per 15–25 cm pot. Good spacing reduces humidity around foliage, helping keep plants tidy and resilient. Pinching early encourages bushiness, allowing each plant to fill its allotted space without overcrowding neighbours.

How do I pinch and harvest purple basil for more leaves without harming the plant?

Begin pinching once seedlings have 4–6 true leaves: remove the top growing tip just above a leaf node to promote two new side shoots. Continue to pinch regularly to keep plants bushy and delay flowering. For harvesting, take individual leaves or snip soft stems above a node with clean scissors, leaving at least one-third of the foliage to fuel regrowth. Avoid stripping entire stems bare. If flower buds form, pinch them off to maintain leaf production; allow a few to bloom later if you wish to save seed or support beneficial insects.

Does purple basil attract pollinators?

Yes. When allowed to flower, purple basil produces nectar-rich blooms that draw bees, hoverflies, and other beneficial insects. The ornamental purple foliage paired with violet flowers is particularly attractive in pollinator-friendly plantings. For maximum leaf yield and flavour, many growers delay flowering by regular pinching; however, letting a few plants bloom toward the end of the season balances harvest with ecological value. In long, warm seasons, plants that set seed may self-seed lightly, though seedlings will still need warm conditions to thrive.

Information on this page summarises typical cultivation practices for the species and is intended as general guidance. Conditions vary by microclimate, soil type, drainage, and exposure, so timing and techniques may need adjustment—for example, sowing after the last frost or when soil is workable. For the most accurate directions, refer to the specific product page for that seed, which includes any tailored instructions provided by the grower and applies to the item you receive.

Cultivation Notes for Purple Basil

Ocimum basilicum var. purpurascens, often called purple basil, rewards careful, warm-season sowing. Start seeds indoors 4–6 weeks before conditions allow transplanting, or direct sow when soil is consistently warm and all danger of frost has passed. Sow shallowly, barely covering, as light aids germination. Keep evenly moist, not waterlogged. Provide warmth and bright light to prevent leggy growth. Transplant when seedlings have several true leaves, spacing 25–30 cm apart in a sunny, sheltered site with free-draining, fertile soil. Pinch growing tips to encourage bushiness and delay flowering. In hot spells, mulch to conserve moisture; in cooler periods, protect from cold winds. Regularly remove flower spikes to maintain leaf production. In mild climates, autumn sowing may be possible under cover, but protect from chills and prolonged wet. For container culture, use a porous mix and avoid oversized pots early on. Save a few plants for seed at season’s end to maintain a preferred line.