Siam Queen Thai Basil (Ocimum basilicum var. thyrsiflora) Seeds

Siam Queen Thai Basil (Ocimum basilicum var. thyrsiflora) is a striking, aromatic basil variety with tall upright growth, dark purple stems, and pink-lavender flower clusters. This non-GMO annual thrives in warm climates and excels in sunny borders, herb garden designs, container plantings, and raised beds. Its flower spikes attract bees and other beneficial pollinators, making it a standout ornamental herb for summer landscapes.

Features

• Tall, upright basil with purple stems and flower spikes
• Non-GMO Ocimum basilicum var. thyrsiflora
• Excellent for containers, borders, and raised beds
• Highly aromatic foliage for sensory and ornamental gardens
• Flower clusters attract bees and pollinators
• Strong, vigorous summer grower

Specifications

• Common Name: Siam Queen Thai Basil
• Scientific Name: Ocimum basilicum var. thyrsiflora
• Plant Type: Annual
• USDA Zones: 4–11 (warm-season annual)
• Season: Late spring through summer
• Height: 16–30 inches
• Foliage: Bright green aromatic leaves, purple stems
• Bloom Color: Pink-lavender flowers
• Heirloom: Yes
• GMO Status: Non-GMO
• Organic: Not certified organic
• Light Requirements: Full sun
• Soil Preference: Rich, well-drained garden soil
• Water Needs: Moderate; consistent moisture
• Growth Rate: Fast
• Days to Maturity: 60–75 days
• Heat Tolerance: Excellent
• Cold Tolerance: Poor; frost sensitive
• Plant Spacing: 12–14 inches
• Seed Longevity: 3–5 years stored cool & dry

Planting Guide 

• Sowing Method: Start indoors or direct sow after frost.
• Seed Preparation: No pre-treatment required.
• When to Plant:
• Indoors: 4–6 weeks before final frost
• Outdoors: After soil warms and frost is gone
• Sowing Depth: 1/8 inch; lightly press and cover.
• Germination Time: 7–14 days with warmth.
• Light Requirements: Full sun for upright, vigorous growth.
• Soil Conditions: Use loose, nutrient-rich, well-draining soil.
• Watering: Maintain even moisture; avoid waterlogging.
• Maintenance:
• Pinch tips for branching and denser foliage
• Remove early flower spikes for extended leaf growth
• Avoid overwatering in containers