What are the sun requirements for Ocimum basilicum 'Purple'?

Ocimum basilicum 'Purple' is purple basil (Dark Opal basil), an annual herb growing 12-24 inches (30-60 cm) tall and 8-12 inches (20-30 cm) wide. Deep purple to burgundy oval leaves 2-3 inches (5-7 cm) with serrated margins. Square stems with purple-red tinting. The purple color is from anthocyanin pigments — develops in full sun. In the mint family (Lamiaceae). The clove-like aroma is released when leaves are bruised. White to pale pink tubular flowers in terminal spikes — pinch to extend leaf production; flowering makes leaves bitter. Open-pollinated — seed can be saved. Tender annual — killed by the first frost. Blackens below 50°F (10°C). Susceptible to Fusarium wilt (Fusarium oxysporum f. sp. basilicum) and downy mildew (Peronospora belbahrii) — the two primary diseases that limit basil production. Direct-sow after last frost or start indoors 6 weeks early. Harvest by cutting stems above a leaf node. Non-toxic (edible herb). Not deer-resistant. Full sun (6+ hours). Growth rate is fast.

Native Range

Open-pollinated cultivar. The species O. basilicum is native to tropical regions of central Africa and southeast Asia (India through New Guinea).

Suggested Uses

Grown in vegetable gardens, herb gardens, and containers of at least 1 gallon (4 L). Edible herb — culinary and ornamental. Tender annual. Open-pollinated — save seeds. Non-toxic. Not deer-resistant.

How to Identify

Identified by deep purple to burgundy oval leaves with serrated margins on square stems with purple-red tinting. The purple foliage, the clove-like aroma when bruised, and the square stems (mint family) are diagnostic. Distinguished from green basil by the anthocyanin-darkened foliage. In Lamiaceae.

Appearance

Size & Dimensions

Height1' - 2'

Width/Spread8" - 1'

Reaches mature size in approximately 1 years

Colors

Flower Colors

Foliage Colors

Fall Foliage Colors

Bloom Information

Bloom Period

~8 weeks

Summer

Summer (July-September). White to pale pink tubular flowers in terminal spikes. Pinch flower spikes — flowering makes leaves bitter. Self-pollinating. If allowed to flower, seed matures in 4-6 weeks.

Detailed Descriptions

Flower Description

White to pale pink, tubular, in terminal spikes — pinch to extend leaf production

Foliage Description

Deep purple to burgundy, oval to lance-shaped, 2-3 inches (5-7 cm) long, with serrated margins; purple-bronze new growth; square stems with purple-red tinting (mint family trait)

Growing Conditions

Sun Requirements

Full Sun

Requires 6-10 hours of direct sunlight daily

• Full Sun: 6+ hours of direct sunlight

• Partial Shade: 3-6 hours of direct sunlight

• Full Shade: Less than 3 hours of direct sunlight

Soil Requirements

pH Range6.0 - 7.0(Neutral)

357912

Soil Types

loam

Drainagemoist

Water & Climate

Water Needs

Medium

Frost Tolerance

tender

Time to Maturity

60-90 days from seed

Care & Maintenance

Care Guide

Full sun (6+ hours). Rich moist soil pH 6.0-7.0. Tender annual — killed by first frost, blackens below 50 degrees F (10 degrees C). Pinch flower spikes. Susceptible to Fusarium wilt and downy mildew. Open-pollinated — save seeds. Non-toxic. Not deer-resistant.

Pruning

Pinch flower spikes as soon as they appear. Harvest by cutting stems above a leaf node to encourage branching. Regular pinching produces a bushier plant. Remove any yellowed or diseased leaves.

Pruning Schedule

summerfall