How to grow Sweet Pepper (Marconi Red)

Capsicum annuum

🥕 Vegetable 🌱 Grown each year

Sweet Pepper Marconi Red is an Italian type variety with a mild, sweet flavour and medium thick flesh. The long, slender peppers (approx. 6cm x 17cm) mature from green to red and are excellent in salads, for stuffing, or roasting. Best grown in a greenhouse or polytunnel with heat, but can be grown outdoors in warm, sheltered locations, though crops may be smaller. Suitable for containers with adequate watering, warmth, and sun. Treat like a greenhouse tomato for best results.

At a glance: Sow mid May to mid June, harvest from late August.

When to sow, plant and harvest

JanFebMarAprMayJunJulAugSepOctNovDec

Sow outdoors

Flowers

Harvest

Timed for a typical UK garden (last frost mid-April). The app uses your own town's frost dates.

Growing Sweet Pepper (Marconi Red): what it needs

Light: Full sun · 8+ hours a day
Watering: Regularly, keep soil moist
Soil: Rich, fertile, well-draining · pH 6.0–6.8
Spacing: 45-60cm apart
In pots: Grows well in containers
Feeding: Feed with a nitrogen-rich fertilizer (e.g., tomato feed) once a week when fruiting begins.
Harvest: About 90 days from sowing
Hardiness: USDA zones 3–11
Difficulty: Intermediate

Step by step

Mid May – mid June · 4 weeks after the last spring frost
Direct Sow Seeds Outdoors (Optional) (optional)
Direct sow in sheltered, fertile soil after all danger of frost has passed and soil is warm. Crops may be smaller and ripen later.
21–28 days after “Sow Seeds Indoors” · Early June – mid June
Check Germination
Seedlings can be slow to emerge, typically 21-28 days. Ensure consistent warmth and light once sprouted, whether indoors or outdoors.
21 days after “Transplant to Final Position” · Late June
Provide Support & Pinch Out
Stake or cage plants as they grow. Pinch out the growing tip to encourage a bushier plant and earlier fruits, or grow as cordons with support.
14 days after “Provide Support & Pinch Out” · Early July
Assist Pollination
Lightly brush flowers with a paintbrush, moving from one flower to the next, to help stimulate pollination and fruit set.
14 days after “Assist Pollination” · Late July
Start Feeding
Begin watering with a nitrogen-rich feed (like tomato feed) once a week when fruiting has begun.
30–90 days after “Start Feeding” · Late August – late October
Harvest Peppers
Harvest from June to September. Peppers can be picked and eaten when green, or left to ripen fully to red. Regular picking encourages more fruits.