When to plant Marrows in London

Sow seeds on their edge around 14th March - 21st March in small pots of warm seed compost. Keep them at 21–24 °C and do not sow too early, because marrow seedlings grow fast and can suffer if they become root-bound.

When the first true leaves appear, prick out or move each seedling into a larger pot at 28th March - 18th April. Handle them gently and keep the compost just moist, not wet.

From 4th April - 25th April, move the plants outside for short periods each day so they adjust to wind, cooler nights and direct sun. Keep them under fleece or in a cold frame at night if conditions are still unsettled.

Set plants out at 18th April - 25th April once frost risk has passed and the soil is warm. Plant into rich, well-watered mounds or pockets, then water in thoroughly without wetting the stem.

From 2nd May - 24th June, keep the plants centred on their mound and tuck the stems back if they stray. In a small garden, use a short frame or straw to keep fruit off damp soil and reduce rot.

From 18th May - 10th November, water deeply around the plant rather than over the leaves, and feed every 14 days once the first fruits set. Keep the compost or soil evenly moist so the fruit fills properly and avoids bitterness.

Pick fruits from 17th June while they are still young and tender, then keep harvesting regularly until 10th November. Cut them with a knife or secateurs so you do not damage the stem, and check plants every few days. Do not eat any fruit that tastes unusually bitter; discard the fruit and remove the plant.