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

Ocimum basilicum 'Cardinal' is Cardinal basil, an annual herb growing 12-18 inches (30-45 cm) tall and 8-12 inches (20-30 cm) wide. Deep green glossy oval leaves 2-3 inches (5-7 cm) with serrated margins. Cardinal red to burgundy tubular flowers in terminal spikes — the red flower color is the cultivar's defining trait; most basil cultivars have white or pink flowers. Square stems (mint family). In the mint family (Lamiaceae). The clove-like aroma is released when leaves are bruised. Open-pollinated — seed can be saved. The red flowers can be allowed for ornamental value or pinched to extend leaf production — the trade-off is that leaves become slightly bitter when flowering. Tender annual — killed by first frost, blackens below 50°F (10°C). Susceptible to Fusarium wilt (Fusarium oxysporum f. sp. basilicum) and downy mildew (Peronospora belbahrii). Direct-sow after last frost or start indoors 6 weeks early. 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.

Suggested Uses

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

How to Identify

Identified by deep green glossy oval leaves on square stems with cardinal red to burgundy tubular flowers in terminal spikes. The red flower color distinguishes Cardinal from other basil cultivars (which have white or pink flowers). In Lamiaceae.

Appearance

Size & Dimensions

Height1' - 1'6"

Width/Spread8" - 1'

Reaches mature size in approximately 1 years

Colors

Flower Colors

red

burgundy

Foliage Colors

green

Fall Foliage Colors

no change

Bloom Information

Bloom Period

~10 weeks

Summer Fall

Summer to fall (July-October). Cardinal red to burgundy tubular flowers in terminal spikes. The red flowers attract pollinators. Pinch to extend leaf production or allow for ornamental value.

Detailed Descriptions

Flower Description

Cardinal red to burgundy, tubular, in terminal spikes — the red flower color is the cultivar's defining trait; differs from the white or pink flowers of most basil cultivars

Foliage Description

Deep green, glossy, oval, 2-3 inches (5-7 cm) long with serrated margins; square stems (mint family)

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 - 7.5(Neutral)

357912

Soil Types

loam

Drainagewell drained

Water & Climate

Water Needs

Medium

Frost Tolerance

tender

Time to Maturity

55-70 days from seed

Care & Maintenance

Care Guide

Full sun (6+ hours). Well-drained soil pH 6.0-7.5. Tender annual — killed by first frost, blackens below 50 degrees F (10 degrees C). Pinch or allow red flowers. Susceptible to Fusarium wilt and downy mildew. Open-pollinated — save seeds. Non-toxic. Not deer-resistant.

Pruning

Pinch flower spikes to extend leaf production, or allow the red flowers for ornamental value. Harvest by cutting stems above a leaf node to encourage branching. Remove yellowed or diseased leaves.

Pruning Schedule

summerfall