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Courgettes are a summer favourite that produce masses of fruit so you'll only need a couple of plants for most households.
January | February | March | April | May | June |
SOW | SOW/PLANT | SOW/PLANT | |||
July | August | September | October | November | December |
PLANT/HARVEST | HARVEST | HARVEST |
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Variety name | Colour | Overall rating | Yield | Germination | Ease of picking | Harvest period |
---|---|---|---|---|---|---|
'Coucourzelle' | Green | |||||
'Defender' | Yellow | |||||
'Dunja' | Green | |||||
'Easy Pick Gold' | Yellow | |||||
'Gold Rush' | Yellow | |||||
'Golden Dawn III' | Green | |||||
'Lungo Fiorentino' | Green |
The more stars the better Yields are an average from three plants Overall rating ignores price and is based on: yield 60%; harvest period 20%; ease of picking 15% and germination 5%
Pay £36.75 for the first year and get the garden you want for less
Get this offerCourgettes are very sensitive to frost. Sow the seeds in late April or early May, no more than four weeks before it’s safe to plant outside in your area. Sow the large seeds individually into 7cm pots of a Best Buy compost for sowing seeds in a heated propagator or on a warm windowsill at about 20ºC. For most households, two plants will produce more than enough fruit.
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Dig a hole about 30cm in depth and diameter. Fill it with a mixture of soil and garden compost or well-rotted manure, leaving a slight mound. Wait until the danger of frost has completely passed before you plant out in late May or early June. By this time, the young plants should have at least one large leaf.
Some varieties are compact enough to grow in pots, such as 'Sure Thing' and 'Patio Star'. Use a container that has a volume of at least 10L and use a Best Buy compost for containers mixed with a Best Buy controlled-release fertiliser. Check if the compost feels dry to the touch every day and water thoroughly when needed. Feed plants in containers with a tomato food (high in potash) to encourage fruit.
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Cover them with fleece until they are growing strongly.
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In dry weather, water every 2 to 3 days with a decent amount. When it's hot, each plant can produce one or even two courgettes every day, when there is plenty of moisture around the roots.
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Harvest in: July to September
Harvest the fruits when they reach 10-15cm long, or even smaller, to avoid a glut. If any fruit get missed and grow too large, cut them off to encourage the plant to produce more fruit.
Powdery mildew usually appears in late summer or early autumn as the plants start to run out of steam. You will first see a white dusting on the leaves, which gradually becomes more severe, before the leaves turn yellow and die.
Read more about powdery mildew.
White or sometimes almost silvery smooth-surfaced patches of discolouration on perfectly good, healthy and green leaves often cause unnecessary concern. Many varieties of courgette and marrow have this appearance and it is perfectly normal and nothing to worry about as it is just a varietal characteristic. Yellow-fruited varieties may also produce yellow leaves and again are nothing to worry about.
The fruits start to develop normally and then, when still quite small, start to discolour and rot at the flower end. The rot then spreads back along the fruit towards the stem. This invariably starts when the petals of the fading flower start to deteriorate and the rot then spreads into the fruit. The petals rot fairly easily and very rapidly during wet weather.
To prevent it happening, always apply water direct to the base of the plants and avoid wetting the flowers, never water from overhead. In wet weather remove the flowers as soon as the fruit has started to form and that way the problem cannot start.
Courgettes, squash and their relatives are all thirsty plants and if they are to perform well they need a fair amount of feeding, too. During dry conditions the plant conserves energy by changing the proportion of male to female flowers. If the soil is too dry they produce more male flowers and, as a result, the crop levels can be dramatically reduced.
Good soil improvement before planting, plenty of water, and the use of a deep mulch with soil improver to conserve soil moisture during the growing season will all help to reduce the problem.
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Courgettes, squash and their relatives are prone to virus infections and symptoms include yellowing, poor growth, stunting and mosaicing, ring-spotting and streaking of the foliage, usually combined with a very poor or non-existent yield. The most commonly seen virus is cucumber mosaic. Viruses are usually spread by handling, or by sap-sucking pests, such as greenfly, as they feed.
Unfortunately, any fruits which do form on virus-affected plants tend to be small, pitted and very unpleasant to eat. If suspect plants appear, remove and dispose of them promptly, but always wash your hands thoroughly after handling virusy or suspect plants.
There are no controls available for virus infections, so avoidance is the key. Check plants regularly and control any pests found. The following year, try to grow virus-resistant varieties, such as courgette 'Defender'.