Courgette Seeds in Ireland

How to sow courgette seeds

Sow one seed to a 9cm pot of multipurpose compost, about 2cm deep, and push it in on its edge rather than flat. The flat side of a courgette seed holds water against the seed coat and rotting is the commonest reason a sowing fails.

Water the compost before sowing, then leave it alone until the seedling appears. Courgette seeds are large and fleshy and they rot in cold wet compost far more readily than they dry out. Keep the pot at 18 to 25C, which in practice means indoors on a warm windowsill or in a heated propagator, not an unheated greenhouse in April.

Germination takes five to ten days. As soon as the loop of stem breaks the surface, get the pot into the brightest place you have, because a courgette seedling stretches fast in poor light and a long floppy stem is hard to plant well.

There is no need to sow early. A plant sown in late April will be ready to go out at the end of May, which is the earliest it is safe anywhere in Ireland outside a sheltered southern garden. Sow a second pot ten days after the first as insurance against slugs.

From June you can sow straight into the ground where the plants are to grow. Put two seeds in each station and pull the weaker one. Direct sowing in May only works under a cloche in a warm sheltered garden in the south east.

Growing on in Irish conditions

Pot the seedling on into a 1 litre pot as soon as roots show at the drainage holes, and grow it until it has four or five true leaves and a stem thick enough to survive an encounter with a slug.

Harden off over a week to ten days before planting out. Courgettes go outside once the frosts have finished: the very end of May on the south coast, the first week of June for most of the country, and mid-June inland and in the north west if the spring has been cold.

Give each plant 90cm of space in every direction. It looks absurd in June and it is exactly right by August, and crowding is what turns a mild dose of mildew into a dead plant. Dig a generous amount of well-rotted manure or compost into each planting position, because courgettes are hungry and thirsty in equal measure.

Shelter matters more than most seed packets admit. Those huge soft leaves catch the wind, and a plant that rocks in an Atlantic gale tears its own leaf stalks and loosens its roots. A hedge, a fence or even a temporary windbreak of mesh on stakes makes a visible difference in an exposed garden.

Cover newly planted courgettes with fleece or a cloche for the first two weeks. It buys warmth at the point in the season when they most need it, and it keeps the slugs and the wind off while the plant establishes.

Water deeply at the base twice a week rather than lightly every day, and keep the water off the leaves. Once fruit is setting, a weekly high potash feed keeps the plant cropping into September.

Harvesting

Start cutting when the fruit reaches 10 to 15cm, and cut rather than pull, using a knife and leaving a short stub of stalk. From mid-July onwards check the plant every two or three days, because courgettes go from perfect to marrow in less than a week in warm weather.

Picking is not just about quality, it is how you keep the plant productive. A maturing fruit signals that the plant has finished its job and flowering slows accordingly. Keep cutting, including any fruit that has started to rot at the tip, and the plant keeps going.

Wear a long sleeve. The leaf stalks carry fine prickles that leave an itchy rash on bare forearms after ten minutes of picking, which is the detail nobody mentions until it has happened to you.

Cropping usually finishes in late September or early October, when mildew and cold nights between them shut the plant down. The last few fruit can be left to swell into marrows for storage if you want them.