PlantSowGrow
How to grow Basil (Sweet Genovese)
Ocimum basilicum
The classic large-leaved Italian basil for pesto, tomatoes and salads. Loves warmth — happiest on a sunny windowsill or in a greenhouse.
At a glance: Sow early May to mid June, harvest from late June.
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 Basil (Sweet Genovese): what it needs
- Light
- Full sun · 6+ hours a day
- Watering
- Water in the morning, at the base; never leave standing in water
- Soil
- Fertile, well-drained soil
- Spacing
- 20 cm
- Height
- 30 cm
- In pots
- Grows well in containers
- Feeding
- A liquid feed every two weeks for pot-grown plants
- Harvest
- About 55 days from sowing
- Hardiness
- USDA zones 10–11
- Difficulty
- Easy
Step by step
- Early May – mid June · 3 weeks after the last spring frost
Sow Seeds Outdoors
Sow thinly in shallow drills where they are to grow. Barely cover the seed and keep at 18–25°C.
- 5–10 days after “Sow Seeds Indoors” · Mid May
Check Germination
Seedlings should appear in 5–10 days. Keep the compost moist. If sown outdoors, thin to 20 cm apart.
- 45–66 days after “Check Germination” · Late June – mid July
Start Harvesting
Pick the top pairs of leaves just above a leaf joint; this makes the plant branch. Take a photo for the journal.
- 21–35 days after “Start Harvesting” · Mid July – late July
Pinch Out Flower Buds
Pinch out flower buds as soon as you see them — flowering makes the leaves bitter.
- Mid October – early November · around the first autumn frost
End of Season
When plants run to seed or the frost gets them, pull them up for compost — leave a few to self-seed if you like.
