For once I am actually growing mine in the recommended sized pot which is 10″/25cms. You can add up to 30% manure to your compost as they like very rich soil, I did not have any so I added a small hand full of pelleted organic chicken manure and will feed with organic liquid seaweed which will hopefully make up for the lack of manure.
You can sow courgette seeds indoors in March and April, outdoors May and June, so you can still sow some seeds. They usually take about 8 – 18 days to germinate, it should be nearer 8 days this time of year. I normally sow mine in 3″ pots and transplant into the 10″ pot when they look like they have outgrown the small one. If you sow them early in the year do not plant out until late spring and all chance of frost is gone as they are very tender. Although it is not so much of a problem if you are growing them in pots as you can just bring them indoors for the night if frost is forecast.
They like a position in full sun if possible but don’t let them dry out in hot weather. I have mulched my pots with bark or stones, it is amazing the difference mulching the pots makes, you don’t realise quite how much water is lost due to evaporation. I tend to decide if they need watering or not by the weight of the pot as I normally water them by sticking them in a big bucket of water and letting them soak up what they need. Or you can poke your finger into the compost and check if it is still damp, if the leaves are starting to wilt water straight away.
I start to feed mine once a week or so with liquid organic tomato fertiliser once the courgettes start to form. If the compost is very dry water with plain water first or you could scorch the roots.
If you have grown courgettes before you will know that they tend to trail along the ground frequently growing at least a couple of inches a day with the courgettes forming all along the new growth. So to solve the problem of having them trailing all over the place I am going to grow mine up canes. I will put 3 or 4 pots together with a cane in each pot and tie the canes together at the top to make a wigwam. As the courgettes grow tie them to the cane preferably using that soft green garden string, as it does less damage to the plants, it is about 70p for a ball of it from the home and garden shop that I can’t remember the proper name of in Pier Street. Pinch out the tips when they reach the top of the canes.
Harvest your courgettes when they are no more than 6″ long by cutting them off with a sharp knife. Towards the end of the season you can let a few of them grow bigger so you have marrows.
Courgettes are extremely versatile they can be grated and eaten raw in salads, cooked as a side dish and there is a huge range of recipes in which they feature as the main ingredient.
Marigolds and nasturtiums are good companions for courgettes
Pests and diseases.
The most common problem that you will encounter growing courgettes is mildew caused by poor air-flow and dry roots. If it gets really bad you can spray the plants weekly with Potassium Bicarbonate or if all else fails Bordeaux Mixture which is copper sulphate and slaked lime both are available from The Organic Gardening Catalogue.
Slugs are very fond of young young courgette leaves but you do have less trouble with them in containers. A circle of salt on the ground around the pots in dry weather does tend to solve the problem.
They are also prone to cucumber mosaic virus which is spread by sap feeding insects, the worst culprit being aphids. The disease causes mottled, puckered leaves that eventually turn yellow and the courgettes go sort of lumpy and shrivelled. Keep plenty of plants that encourage beneficial insects near to them and eliminate aphids as soon as you see any. There is no cure for this disease, you can buy mosaic resistant varieties but it is no guarantee.