Back to growing guides
Z
FlowersHalf-HardyAnnual
Zinnia
Zinnia is a half-hardy annual grown for brilliantly coloured daisy and dahlia-like flowers on sturdy stems, making it one of the best late-summer cut flowers. It thrives in heat and sun, and modern varieties offer strong disease resistance and excellent garden impact.
Basic information
Category
Flowers
Lifecycle
Annual
Hardiness
Half-Hardy
Planting partners
0 companions · 0 crops to avoid
Growth profile
Germination window
7–10 days
Germination temperature
20–24 °C
Plant spacing
25 cm
Row spacing
35 cm
Sowing depth
0.5 cm
Height
90 cm
Spread
25 cm
Calendar
JJan
FFeb
MMar
AApr
MMay
JJun
JJul
AAug
SSep
OOct
NNov
DDec
Sow Indoors
Sow Outdoors
Plant Out
Flowering / Harvest
Timings based on average frost dates in the UK. Sign up to set your frost dates.
Care tips
Raise zinnias with warmth and plant them into full sun only after nights have become reliably mild. Space plants well for airflow, deadhead or cut blooms frequently, and avoid wetting the foliage late in the day if mildew has been a problem before.
Common pests
Slugs, aphids, powdery mildew, botrytis in crowded damp growth.
Companions
No companion crops have been added yet.
Don’t grow with
No crops to avoid have been added yet.