Ocimum basilicum 'African Blue'
African Blue Basil
A sterile hybrid of O. basilicum × O. kilimandscharicum (camphor basil); the parents are native to tropical Africa and AsiaKey Features
Maintenancelow
Overview
Ocimum basilicum 'African Blue' is African Blue basil, a sterile hybrid annual herb growing 36-48 inches (90-120 cm) tall and 18-24 inches (45-60 cm) wide — the largest basil cultivar commonly available (36-48 inches / 90-120 cm vs. 12-18 inches / 30-45 cm for sweet basil). Green leaves with purple-tinged veins and undersides, oval to lance-shaped, 2-3 inches (5-7 cm). Dense purple-blue terminal flower spikes 6-8 inches (15-20 cm) from late summer through fall — a pollinator nectar source. In the mint family (Lamiaceae). A sterile hybrid of O. basilicum × O. kilimandscharicum (camphor basil from East Africa). Sterile: does not set seed — must be propagated by stem cuttings. Unlike most basil cultivars, the leaves maintain their flavor during flowering — the flower spikes do not need to be removed for leaf quality. The aromatic profile is more complex than sweet basil: sweet, spicy, and camphor-like. Cold-sensitive: blackens at the first touch of frost or temperatures below 40°F (4°C). Perennial in zones 9-11 (where it can reach 4-5 feet / 120-150 cm), annual elsewhere. Start from cuttings or purchased transplants (seed not available — sterile hybrid). Non-toxic (edible herb). Full sun. Growth rate is fast.
Native Range
A sterile hybrid of O. basilicum × O. kilimandscharicum (camphor basil). The parent species are native to tropical Africa and Asia.Suggested Uses
Grown in herb gardens, borders, and containers of at least 5 gallons (19 L). The largest common basil cultivar. Purple-blue flower spikes for pollinator gardens. Sterile — propagate by cuttings. Leaf flavor maintained during flowering. Non-toxic. Annual (perennial zones 9-11).How to Identify
Appearance
Size & Dimensions
Height3' - 4'
Width/Spread1'6" - 2'
Reaches mature size in approximately 1 years
Bloom Information
Late summer to fall (August-November). Dense purple-blue terminal flower spikes 6-8 inches (15-20 cm). Pollinator nectar source. Unlike most basil, leaf flavor is maintained during flowering.Detailed Descriptions
Flower Description
Purple-blue, tubular two-lipped, in dense cylindrical terminal spikes 6-8 inches (15-20 cm)Foliage Description
Green with purple-tinged veins and undersides; oval to lance-shaped, 2-3 inches (5-7 cm); aromatic — a complex blend of sweet, spicy, and camphor-like notesGrowing Conditions
Sun Requirements
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
Care & Maintenance
Care Guide
Full sun (6+ hours). Moist well-drained soil pH 6.0-7.5. Sterile hybrid — propagate by stem cuttings (no seed). Cold-sensitive — blackens below 40 degrees F (4 degrees C). Leaf flavor maintained during flowering. The largest common basil cultivar. Complex aroma (sweet, spicy, camphor). Non-toxic. Annual (perennial zones 9-11).Pruning
Pinch growing tips for bushier growth. Harvest leaves by cutting stems above a leaf node — the plant regrows from the node. Flower spikes do not need removal (leaf flavor maintained). Take stem cuttings for propagation before frost.Pruning Schedule
J
F
M
A
M
J
J
A
S
O
N
D
summerfall
Maintenance Level
lowContainer Growing
✓ Suitable for container growing
Minimum container size: 5 gallons
⚠️ Toxicity Warning
Non-toxicPlanting Guide
Planting Methods & Timing
Planting Method
transplant
Indoor Start
6 weeks before last frost
Direct Sow Timing
After last frost when soil temperature reaches 60 degrees F (16 degrees C)+
Days to Maturity
80–90 days
Plant Spacing
18 inches