Cleome houtteana
spider flower
SunFull Sun – Part Shade
Overview
Cleome houtteana, spider flower, is a tall, erect annual in the Cleomaceae, growing 3-5 ft (90-150 cm) tall on a single stout, glandular-hairy, often spiny stem. The palmately compound leaves have five to seven lance-shaped leaflets and small spines at the leaf bases, and the foliage carries a pungent scent when bruised. From early summer until frost it bears domed, elongating clusters of flowers, each with four clawed petals and very long, projecting stamens that give a spidery look. Flower color ranges from rose-pink and lavender to white. As the cluster lengthens, slender seed pods 2-4 in (5-10 cm) long stand out below the open flowers on long stalks. Cleome houtteana is native to southern South America and is widely grown as a warm-season bedding annual elsewhere. It self-seeds freely and can naturalize or become weedy where summers are long. The plant tolerates heat, drought, and poor soil once established but flops in rich, overwatered ground and shaded sites. The spiny stems and strong odor make it unappealing to deer.
Native Range
Native to southern South America, including southern Brazil, Paraguay, Uruguay, and northern Argentina. It grows in open, disturbed, sunny ground and is widely cultivated and naturalized beyond its native range.Suggested Uses
Used at the back of summer borders, in cottage and cutting gardens, and in large mixed containers. Suited to hot, sunny beds and pollinator plantings that draw bees, butterflies, and night-flying moths. Combines with other tall warm-season annuals.How to Identify
Appearance
Size & Dimensions
Height3' - 5'
Width/Spread1' - 2'
Bloom Information
Detailed Descriptions
Flower Description
rose-pink, lavender, to whiteFoliage Description
greenGrowing Conditions
Sun Requirements
Requires 6-12 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
Water & Climate
Water Needs
Drought Tolerance
Drought tolerant when established
Care & Maintenance
Care Guide
Grows in full sun and average, well-drained soil with pH 6.0 to 7.5. It tolerates heat, drought, and poor ground once established and flowers most freely when not overwatered. Seed can be sown directly after the last frost or started indoors about six weeks earlier, and germination improves with alternating warm and cool temperatures. Plants self-seed heavily, so removing some seed pods limits volunteers. Rich soil and shade produce tall, floppy growth that may need support.Pruning
Pruning is limited to removing spent flower stalks. Cutting off developing seed pods extends bloom and reduces self-sowing. Pinching young plants once encourages branching and more flower stems.Container Growing
✓ Suitable for container growing
Minimum container size: 5 gallons
✓ Toxicity
Non-toxicPlanting Guide
Planting Methods & Timing
Planting Method
both
Indoor Start
6 weeks before last frost
Direct Sow Timing
Sow after the last frost when soil is warm
Days to Maturity
70–85 days
Plant Spacing
18 inches