Zinnia
Don't hurry it: a zinnia sown or planted into cold soil stalls for weeks, while one sown a month later into warm soil overtakes it.
Care
Full sun and warmth — in a cool, grey summer zinnias sulk and flower late.
Medium — water at the base rather than over the leaves, which invites mildew.
Well-drained, fertile soil in a warm position.
Pinch out the growing tip when young plants have three or four pairs of leaves to get more stems. Cut flowers and deadhead regularly — the more you cut, the more it flowers.
A balanced liquid feed every two weeks once flowering starts, especially in pots. In reasonably fertile ground they need little more.
From seed only. Zinnias hate root disturbance, so sow into individual modules or direct where they are to flower, and only once the soil is warm — cold, wet compost rots the seed.
Month by month
Months change with the climate: in southern Italy tomatoes go out two months earlier than in England.
- AprilSow under cover in individual modules with gentle warmth. how ›
- JunePlant out after hardening off, once nights are reliably warm. how ›
- JunePinch out the tips of young plants for bushier growth and more stems. how ›
- AugustCut and deadhead regularly to keep flowers coming. how ›
Months based on climate: UK. Your choice stays on this device.
- AprilSow under cover in individual modules with gentle warmth. how ›
- MayPlant out after hardening off, once nights are reliably warm. how ›
- JunePinch out the tips of young plants for bushier growth and more stems. how ›
- AugustCut and deadhead regularly to keep flowers coming. how ›
Months based on climate: Northern Italy. Your choice stays on this device.
- MarchSow under cover in individual modules with gentle warmth. how ›
- MayPlant out after hardening off, once nights are reliably warm. how ›
- JunePinch out the tips of young plants for bushier growth and more stems. how ›
- AugustCut and deadhead regularly to keep flowers coming. how ›
Months based on climate: Central Italy. Your choice stays on this device.
- MarchSow under cover in individual modules with gentle warmth. how ›
- AprilPlant out after hardening off, once nights are reliably warm. how ›
- JunePinch out the tips of young plants for bushier growth and more stems. how ›
- AugustCut and deadhead regularly to keep flowers coming. how ›
Months based on climate: Southern Italy and islands. Your choice stays on this device.
Common problems
How to spot it. White powdery coating on leaves from late summer.
What to do. Water at the base, space plants for air flow, and choose mildew-resistant varieties.
How to spot it. Young plants grazed to stumps overnight.
What to do. Plant out sturdy plants and protect them for the first weeks.
How to spot it. Seedlings collapse at soil level.
What to do. Sow into warm compost, don't overwater, and give good ventilation.
Questions
Zinnia: is it hardy?
H2: Tender. It survives down to 1 °C.
Can it grow in a pot?
Yes — dwarf varieties are excellent in sunny pots; tall ones are better in the ground.
Zinnia: when do you prune it?
Pinch out the growing tip when young plants have three or four pairs of leaves to get more stems. In the calendar for UK, pruning falls in June.
Zinnia: when does it flower?
In the climate of UK it flowers in July–October.
When do you feed it?
A balanced liquid feed every two weeks once flowering starts, especially in pots. In reasonably fertile ground they need little more. Feeding months, UK: July–September.