How to grow courgettes and summer squash

Summer isn’t summer on the allotment without the easy to grow and abundantly productive courgette. The seeds germinate reliably and the plants grow quickly so they are a good crop for the novice vegetable grower and for getting children involved. Courgettes are available in green, yellow and almost black varieties and can have different patterned skin to add to the interest. Small round varieties are also available. Three plants will be more than enough to feed a family and you will probably have plenty to give to friends too.

Like courgettes, summer squashes such as patty pans belong to the cucurbit family. They require similar growing conditions and are grown in the same way.

Courgettes and summer squashes are not hardy so should be kept under cover until risk of frost has passed.

Sow courgettes and summer squash

Courgettes and summer squash can be sown indoors from late March until May. I usually sow mine in early April.

Sow seeds individually on their edge about 2cm deep in a 5cm pot of multi-purpose compost. Water well. Place in a heated propagator or on a warm, sunny window sill. Ideal germination temperature is about 20C. Once germinated remove from the propagator to a warm window sill. Keep watered. Pot plants on into 10cm pots when necessary.

Courgettes can be also be sown direct in their growing position but remember they are tender and will not survive frosts so this should not be attempted until after your last frost date. I suggest sowing two or three seeds per position as germination is less reliable. Protection with a cloche or fleece is beneficial.

Grow courgettes and summer squash

Courgettes and summer squash can be planted out after the last frost date has passed and when the soil has begun to warm up. Allow about a metre between plants. Dig a hole about 30cm square and 30cm deep. Add some well rotted manure or garden compost to the soil and mix well. Back fill then plant your courgette in the middle. Water in and keep well watered throughout the season.

A liquid feed can be applied every two weeks.

Harvest courgettes and summer squash

Courgettes and summer squash are best harvested young. Courgettes are at their best at about 10cm long, patty pans at about 5cm in diameter. Harvest regularly and they will continue to bear fruit until September or October.

Courgette and summer squash problems

Immature plants are susceptible to slug and snail attack.

Powdery mildew appears as a white fungus-like powder on the leaves which may shrivel and become stunted. Well-watered, healthy plants are less likely to be affected. Ensure adequate spacing to permit good air flow around he plants.

Grey mould is a grey fungal growth which can begin as pale or discoloured patches. It is common in damp or humid conditions. Fungal spores enter the plants through damaged tissue. Damaged parts should be removed and burned. As with powdery mildew good ventilation and generous plant spacing is beneficial.