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Cut flowers7 varieties
Cosmos
Cosmos bipinnatusEasy, branching annual with feathery foliage and prolific daisy-like flowers for cutting and pollinators.
Days to maturity
75–90 daysDays to germ.
7–21 daysSpacing
4–12 inHeight
36–60 inSun
SunVase life
5–7 daysHow we grow it
Germination
- Days to germ.
- 7–21 d
- Soil temp
- 68–75 °F
- Depth
- 0.125 in
- Light for germ
- light
Culture
- Days to maturity
- 75–90 d
- Spacing
- 4–12 in
- Height
- 36–60 in
- Sun
- Sun
- Frost
- Tender; foliage will die back with first autumn frost · tender
Harvest
- Cut stage
- Petals just opening, but not yet flattened.
- Vase life
- 5–7 d
- Notes
- Deadheading is required to have blooms all summer.
Timing · Zone 5a
JanFebMarAprMayJunJulAugSepOctNovDec
Sow indoorsApr 2 – Apr 23
Outdoor / directMay 21 – Jun 18
Bloom (from indoor)May 21 – Jun 14
Bloom (from outdoor)Aug 2 – Sep 18
Windows are anchored to an average last frost of May 21 (1 year in 10 as early as Apr 29, as late as Jun 2) and an average first frost of Sep 18 (1 year in 10 as early as Sep 6, as late as Oct 8). In a late or early year, slide them with it.
Compare in the calendarTrials
Every Cosmos sowingSeed sources, counts, ratings, and the observations kept against each one.Cosmos trials- Suits
- PinchPinch at 6-9" to encourage branching.
- Cut-and-Come-AgainWill bloom until frost if cut.
- Not for
- Succession
Varieties
7 varieties on recordNo photograph yetCosmos ‘Double Click Cranberries’
‘Double Click Cranberries’
Cranberry Red
‘Apricotta’
Apricot/Peach to RoseNo photograph yetCosmos ‘Candy Stripe’
‘Candy Stripe’
Pink · White · Dark PinkNo photograph yetCosmos ‘Cupcake Blush’
‘Cupcake Blush’
Light PinkNo photograph yetCosmos ‘Double Click Rose Bon Bon’
‘Double Click Rose Bon Bon’
Rose PinkNo photograph yetCosmos ‘Double Click Snow Puff’
‘Double Click Snow Puff’
WhiteNo photograph yetCosmos ‘Rubenza’
‘Rubenza’
Dark Red