Photo: "Cosmos Brilliant in Early Autumn Sun" by kiwisrus
· CC BY-SA 2.0
Flower · Companion-annual
Cosmos
Asteraceae
THRIVES in poor soil — plant where nothing else will grow. Exceptional beneficial insect habitat attracting parasitic wasps, tachinid flies, lacewings, minute pirate bugs, ladybugs, spiders. 2-5 ft. Self-seeds freely and prolifically. Rich soil produces foliage over flowers.
At a Glance
Days to Maturity
70–90 days
Sun
6+ hours
Container
Yes
Height
2–5 ft
Zone Planting Guide
Growing Guide
Germination
Germination Time
3–10 days
Optimal Temp
65°F
Watering
Needs
Low
Resilience
Heat: High
Cold: Low
Drought: Medium
Nutrition
Feeding Intensity
Light feeder
Harvest
Flowers/foliage at desired stage
Sources
research
Multiple sources
university_extension
NC State Extension Gardener Plant Toolbox
More Flowers
Cosmos Planting Dates by Zone
Planting dates for Cosmos vary by USDA hardiness zone. Select your zone below for frost dates, start-indoors timing, and a full monthly planting calendar.
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