PlantSowGrow
How to grow Kale (Cavolo Nero)
Brassica oleracea Acephala Group
Tall, dark, crinkled "black kale" from Tuscany with a rich, sweet flavour. Crops from autumn right through winter.
At a glance: Sow mid April to mid June, harvest from late July.
When to sow, plant and harvest
Timed for a typical UK garden (last frost mid-April). The app uses your own town's frost dates.
Growing Kale (Cavolo Nero): what it needs
- Light
- Full sun · 6+ hours a day
- Watering
- Water regularly in dry weather
- Soil
- Fertile, well-drained soil
- Spacing
- 45 cm
- In pots
- Only in large containers
- Feeding
- A general feed before sowing or planting
- Harvest
- About 100 days from sowing
- Hardiness
- USDA zones 3–9
- Difficulty
- Easy
Step by step
- Mid April – mid June · around the last spring frost
Sow Seeds Indoors
Sow in modules or small pots of seed compost under cover.
- 5–10 days after “Sow Seeds Indoors” · Mid April – late April
Check Germination
Seedlings should appear in 5–10 days. If sown outdoors, thin to 45 cm apart when big enough to handle.
- 14–21 days after “Check Germination” · Early May – mid May
Pot On Seedlings
Move seedlings into 9 cm pots (or keep in modules) when they have their first true leaves.
- Mid May · 5 weeks after the last spring frost
Harden Off
Stand plants outside by day for 7–10 days before planting out.
- Late May – late June · 6 weeks after the last spring frost
Plant Out
Plant out 45 cm apart and water in well.
- 0–3 days after “Plant Out” · Late May – early June
Net Against Pests
Cover with fine insect mesh or netting straight after planting to keep off pigeons, cabbage white caterpillars and flea beetles.
- 60–81 days after “Plant Out” · Late July – mid August
Start Harvesting
Pick lower leaves as needed; frost makes them sweeter.
- 180–210 days after “Start Harvesting” · Late January – late February
Finish and Clear
Clear the remains to the compost heap once cropping ends.
