© Katharva, some rights reserved (CC-BY-SA) · Wikimedia Commons
Ocimum × citriodorum
lemon basil
Overview
Ocimum × citriodorum is an annual herb in the Lamiaceae family, a natural hybrid between O. basilicum (sweet basil) and O. americanum (American basil). Plants grow 12–20 inches (30–50 cm) tall and 10–14 inches (25–35 cm) wide with a bushy, compact habit. Leaves are 1–2 inches (2.5–5 cm) long, bright green, smooth, with a strong lemon-citrus aroma and flavour — the citral compound responsible for the lemon scent is the same compound found in lemongrass and lemon verbena. Stems are green, square. Flower spikes are white to pale green, less showy than Thai basil flowers. The lemon flavour is distinct from the clove-anise spectrum of other basils, making lemon basil suited to fish, chicken, and dessert preparations where a lemon-herb character is desired. Days to maturity: 55–65 from transplant. Seed viability declines faster than sweet basil — use fresh seed. In Southeast Asian cuisine (particularly Lao and Indonesian), lemon basil (kemangi in Indonesian) is the standard culinary basil, used differently from Thai basil. Susceptible to the same pest and disease complex as sweet basil — downy mildew, fusarium wilt, and cold damage.
Native Range
Ocimum × citriodorum is a hybrid of tropical Asian origin. Widely cultivated in Southeast Asia, particularly Laos, Indonesia, and the Philippines.Suggested Uses
Culinary — the lemon flavour suits fish, chicken, shrimp, salads, and desserts. Infused in water or tea for a lemon-basil beverage. In Southeast Asian cooking, used in soups (soto ayam), salads (lalab), and as a table herb. In the Pacific Northwest, grown as a warm-season annual alongside other basil types in the herb garden or in containers on warm patios.How to Identify
Appearance
Size & Dimensions
Height1' - 1'8"
Width/Spread10" - 1'2"
Reaches mature size in approximately 1 years
Bloom Information
White to pale green flower spikes from July onward. Less ornamental than Thai basil flowers.
Detailed Descriptions
Flower Description
White to pale greenFoliage Description
Bright greenGrowing 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
Start seed indoors 6–8 weeks before last frost at 70–75°F (21–24°C). Transplant after last frost, night temperatures above 50°F (10°C). Space 10–12 inches (25–30 cm) apart. Full sun, fertile well-drained soil, pH 6.0–7.0. Water 1 inch (2.5 cm) per week. Pinch tips for bushy growth. Use fresh seed — viability declines after 1–2 years.Pruning
Pinch tips every 2–3 weeks. Remove flower spikes to extend vegetative harvest. Harvest by cutting stems back to a leaf pair.Container Growing
Suitable for container growing
Minimum container size: 3 gallons