How to grow courgettes – from a gardener who always kills them

Courgettes are one of the staples of a vegetable garden, they are prolific croppers and supposedly very easy to grow. 

But I’m going to let you in on a dirty little secret of mine: I’ve had an absolute disaster of a time attempting to grow courgettes most years.  

In fact, I have only been successful in my pursuit of these elusive veggies which every other gardener seems to grow with ease about three times. So, I’m here to teach you how NOT to grow courgettes, as I’m pretty sure I’ve done every single thing wrong at one stage or another.

Courgettes, also known as zucchini, are prolific growers, producing two or three courgettes per week in the height of growing season. They grow very well in warm climates, which is why we often associate them with Mediterranean dishes. Courgettes actually originated in Mexico so they need a warm, sheltered spot in order to thrive.

Sowing Courgettes

Courgettes are best started indoors and moved to their final growing spot in June when the chance of frost has passed. Plant one seed about half an inch deep in 7cm pots. The pot size really does matter here as courgettes use up the nutrients in the soil very quickly so don’t plant them in seed modules. Keep the soil moist but don’t over water your courgettes while they are germinating. Keep the pots on a warm windowsill or in a greenhouse or polytunnel. They germinate very quickly in the right temperature, in fact, mine germinated in three days this year and within a week they were pretty large already. 

Fiona’s crimes against courgettes, part one: Not potting on

Because courgettes grow so quickly, they’ll use up the nutrients in these pots in about three weeks, so they need to be potted on. This was my big mistake in year one, I had no idea they would grow so large so quickly and left them in the small pots for about six weeks, causing the plants to become too large for the pots and the stems to snap. Heartbroken. 
You need to transfer your plants to larger pots. 

My second attempt at growing courgettes was going really well. I had potted them on, kept them well watered and the plants were huge. I had decided to grow them outdoors, courgettes do well outside in our climate as long as they are not planted out in cold weather and the plants are hardened off.

Hardening off plants that have been grown indoors is essential if you are transferring them outside – click here for my handy guide to hardening off your seedlings.

I eagerly planted out my courgettes on a warm summer day and within three days, the weather turned colder, my plants went into shock at the temperature change and withered away and died. Devastated.

Fiona’s crimes against courgettes, part three: Not watering regularly

Once established in the ground, courgettes need plenty of water. A few years ago, I was having major success. I had potted them on, hardened them off, planted them out all with success, everything was going swimmingly, until I broke my foot. I was unable to visit my plot regularly, meaning I was unable to water my plot regularly and my beautiful courgettes once again died.

Water them every day, but water the base of the plants to direct the water to the roots. Under-watering courgettes will prevent them from bulking up. 

Pro tip:  It helps to avoid smashing your bare foot off a door frame.

Fiona’s crimes against courgettes, part four: Not spacing them out

Courgettes grow very large, with a huge leaf spread, so need lots of space between plants. Leave about a metre between each plant, this might look a bit ridiculous when they are small plants but trust me, they will take over this space in no time. Their large leaf spread also creates a haven for slugs, which brings me to…

Fiona’s crimes against courgettes, part five: Not protecting my plants

A couple of years ago, I decided to double my chances of success by planting courgettes both outdoors and in the polytunnel. Clever Fiona. Alas, I never foresaw the complete destruction of the polytunnel courgettes by slugs. It is essential to go on regular slug patrol and take whatever steps you can to keep them from your plants, beer traps, coffee grounds, crushed egg shells, whatever it takes.

The great slug demolition was the moment I decided I might have to hang up my trowel. I had been told they were the easiest thing in the world to grow and for three years in a row, I murdered mine from lack of knowledge or proper care.

Care and tips

Because of our temperate climate in Ireland, we often have to give courgettes a helping hand when growing outdoors. If you have the time, make yourself a hot bed for your courgettes. Prepare the bed in spring, dig about a spade’s depth into the bed. Fill the hole up with well-rotted manure and cover with compost. The manure heats up the soil, creating a hot bed for your plants and also provides the fertile-rich soil that courgettes love.

Protect your plants in colder climates with a cloche or plastic sheeting.

They are hungry plants, so they will benefit from mulching. Please, I implore you NOT to use a chemical fertiliser. Use seaweed, comfrey, nettle feed, anything but a chemical-based fertiliser.

Harvesting courgettes

Plants should produce two or three courgettes a week in good conditions. Harvest when they are still small as this is when they taste best. You can, of course, leave the courgettes to grow into huge marrows, but they taste awful and as much fun as it is o grow giant marrows, it’s a bit pointless growing inedible food.

If you’ve any tips for me on growing courgettes, let me know, I need all the help I can get so I don’t end up incarcerated for a courgette serial-killing spree.

Did you know you can eat courgette flowers? They are delicious stuffed with couscous or cheese and tossed in a light batter and fried. Bliss.