Elegant, airy, and wildly colorful, Cosmos are a must-have for both pollinator gardens and natural dye projects.
The Cosmos Mix includes a variety of shades—typically white, pink, and magenta—with delicate, daisy-like blooms and feathery foliage. Easy to grow and drought-tolerant, cosmos thrive in poor soil and bloom nonstop until frost, making them an ideal choice for low-maintenance color and textile experimentation.
Basic Info:
- Common Names: Cosmos, Garden Cosmos, Mexican Aster
- Color (for dyeing): Pink, orange, and yellow varieties offer dye potential (note: pink mix yields subtler tones, while orange types like Cosmos sulphureus give stronger golds)
- Flower Type: Daisy-like composite
- Scientific Name: Cosmos bipinnatus (for most mixes)
Cultivation Info:
- Days to Maturity: 75–90 days
- USDA Hardiness Zone: Grown as annual in Zones 2–11
- Planting Depth: 1/4 inch; lightly covered
- Plant Spacing: 12–18 inches apart
- Growth Habit: Upright and branching; 3–5 feet tall
- Soil Preference: Well-drained, moderately fertile soil (avoid over-fertilization)
- Light Preference: Full sun
Additional Information:
- Taxonomy: Family Asteraceae
- Seed Type: Open-pollinated; often sold as “cut flower mix” or “wildflower blend”
- Sow Instructions: Direct sow after last frost, or start indoors 4–6 weeks early; germinates in 7–10 days at 65–70°F
- Diseases: Powdery mildew, especially in overcrowded plantings
- Pests: Aphids, thrips (usually minimal impact)
Natural Dyeing Use:
Cosmos petals—especially from orange or yellow varieties (Cosmos sulphureus)—can yield vibrant golden yellow dyes. The mix of Cosmos bipinnatus produces subtler earthy pinks and tans when used with alum or iron mordants. Ideal for dyeing wool and silk. Petals can be used fresh or dried, and layering petals with other botanicals offers complex results in bundle dyeing.
Troubleshooting Tips:
- Few Blooms? Avoid rich soil and fertilizer—cosmos thrive on neglect.
- Lanky Growth? Plant in full sun and space generously to reduce leggy stems.
- Mildew? Thin plants and water at soil level to improve airflow.