Plants Bants: How NOT To Grow Courgettes 

Last week, I wrote about how to grow your own strawberries and I received a few requests from readers to feature a post on growing courgettes. Courgettes are one of the staples of a vegetable garden, they are prolific croppers and supposedly very easy to grow. 

I had a brief embarrassing moment a couple of weeks ago. I was at the FoodMatters tent at Bloom festival, giving advice on how to grow vegetables in containers, when an audience member asked me about growing courgettes. 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 every year. Cue me, standing in front of an audience with a microphone, having to admit that I have in fact killed every courgette plant I’ve tried to grow. 

WANTED Notorious Courgette-Killer-Kelly, for crimes against gardening. So scary you might just wet your plants

In fact, this is the first year I have been successful in my pursuit of these elusive veggies which every other gardener seems to grow with ease. So, in this week’s plants bants, I’m going to talk about how NOT to grow courgettes as I’m pretty sure I’ve done every single thing wrong that you can do and as such, am an expert courgette killer.

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 in fact, 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/polytunnel. Courgettes 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 6 weeks, causing the plants to become too large for the pots and the stems to snap. Heart. Broken. 
You’ll need to transfer your courgettes to larger pots. 

Courgettes get too big for their boots (roots?) and need more space to grow. Much like my efforts to squash myself into skinny jeans in winter, there’s no point in squashing your courgettes into tiny pots that don’t fit them anymore. Nobody wants muffin-top plants, and seeing that there’s no weight watchers or slimming world for plants, simply go large or go home. Use a good quality organic, nutrient rich compost and keep your courgettes well watered. Keep the plants indoors until all chances of frosts have passed. Young courgette plants hate frost. This leads me to my next sin…

Fiona’s crimes against courgettes part two: Not hardening off

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.

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

Check out my guide to hardening off your seedlings here.

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

Once established in the ground, courgettes need plenty of water. Two years ago, I was having major success with my courgettes. 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 your courgettes 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

Last year, 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 courgette slug demolition was the moment I decided I might have to hang up my trowel. I’d been told that courgettes where the easiest thing in the world to grow and three years on the trot I’d murdered mine from lack of knowledge or proper care.

This year, all has changed. My courgettes are thriving in the polytunnel. I’m keeping them well watered, protecting them from slugs using coffee grounds (more on that in a later post) and singing to them regularly, it can’t hurt right?

I have of these monsters in the polytunnel

Courgette Crop Care and Tips

Because of our temperate climate, 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 spades 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 courgettes in colder climates with a cloche or plastic sheeting.

Courgettes are hungry plants so will benefit from mulching. Please, I implore you as always NOT to use a chemical fertiliser. Use seaweed, comfrey, nettle feed, ANYTHING but a chemical based fertiliser! 


Plants should produce two or three courgettes a week in good conditions. Harvest the courgettes 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 as its great fun to grow giant marrows, it’s a bit pointless growing inedible food in my humble opinion.

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

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.

0 thoughts on “Plants Bants: How NOT To Grow Courgettes ”

  1. Hi Fiona, Thanks for all the tips, I like the idea of eating the flowers with some cous cous…Yum. I only potted on my courgettes yesterday. I planted them a bit late in the year but I think they will be fine. Also, the seeds expired in 2011 but they still germinated which is cool

  2. How interesting! I, too, have killed my summer squash each year prior to this one. Your instructions sound like my childhood climate. Here the timeline, sunshine, etc is quite different. I think my success this year was for three main reasons: I direct sowed on time for my climate, I found a variety better suited to my area, and we had lake-fulls of rain so my neglectful watering habits couldn’t cause harm. I have three plants and they’ve been keeping us in zucchini for over a month now and show signs of speeding up! Now if I could just remember to spray them with sulfur to help the powdery mildew…

    1. It’s amazing the difference that planting the right variety can make. I’ve never direct sowed courgettes, it’s far too cold here as we can get ground frosts right up until late May. One thing we’re not short on is rain but this year as the courgettes are in the polytunnel I have to water them everyday. I’ve planted four, which is obscene for one person but I tend to always plant more than I need, just in case some of the plants don’t make it. I haven’t experienced powdery mildew on them yet (probably because I invariably kill them before they get the chance ?).

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