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Growing Watermelons In The UK

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If you have spent much time around my blog then you will be well aware that I like to try and grow some more exotic plants every now and again like dragonfruit or sweet potatoes.

It should come as no surprise then that I have also turned my hand to growing watermelons, right here in northern England. Shall we see how I got on?

Can You Grow Watermelons In The UK?

Yes, you definitely can grow watermelons right here in the UK. You can even grow them outside in a lot of the country, although you will need to probably start them indoors.

The earlier you can start watermelons the more likely you are of being successful, this is because they take a long time to fully develop and ripen, up to 80 days!

So if you only started them once the weather was warm enough, say mid may then we would be heading into September before the first fruits were fully ready.

No need to panic though, you can start your seeds earlier but you just need to do it indoors or in a greenhouse. Or if you don’t want to grow them from seed you can buy ready-made plants and just plant them up when they arrive from the grower.

How I Grew My Watermelons

With this being my first time growing watermelons I decided to give myself the best chance of being successful and bought some grafted watermelon plugs from Suttons.

These are watermelon plants grafted onto a different rootstock. This means you normally get more vigorous growth and therefore more chance of being successful.

How The Grafted Watermelons Arrived
How The Grafted Watermelons Arrived

Here are the grafted watermelons when they arrived to me through the post. The plastic clip is a grafting clip and it is where the two plants are joined. The clip is there to hold the graft together while it heals.

Why Grafted Plants?

I grew grafter watermelons this year just for the headstart they give you. Grafted plants tend to be very vigorous as they are grafted onto a very vigorous rootstock.

They are also better croppers than regular plants, the ones I got were from Suttons and they claim they produce an up to 75% bigger harvest. They also have better pest and disease resistance.

The plants I am growing this year are Ingrid watermelons, if you are interested you can find them here.

Growing Watermelons Vertically

I decided to grow my watermelons vertically up support rather than letting them sprawl out along the ground. This is purely to save space in the polytunnel.

I have my watermelons at the back of the bed growing vertically and sweet potatoes growing along the ground in the same bed. This just allows me to get two different crops out of the same bed in summer.

Training My Watermelon
Training My Watermelon

Here you can see how I am growing my watermelons and tying them into this blue rope. The plants will be more than happy to grow like this but as soon as the watermelons start to form I will need to net them to help take the weight.

My watermelons took a while to get going but as soon as the vines started growing out of the centre of the plant they grew at a rapid pace.

The photo below is only a week or two after the one above.

Watermelons Growing In My Polytunnel
Watermelons Growing In My Polytunnel

Male and Female Flowers

Watermelons are members of the cucurbit family along with cucumbers, pumpkins, squash etc and you can really see the resemblance in the way they grow.

Another thing they share with all those other plants is that they develop male and female flowers. The male flowers will never turn into watermelons and are just there to fertilise the female flowers.

It can be important sometimes to be able to tell the difference between male and female flowers if you ever have to hand pollinate the plants.

Female Watermelon Flower
Female Watermelon Flower

What Happened

Well, I got exactly zero watermelons from my plants.

Germination was incredibly poor, and even the few that did germinate never made it to any sort of size before the plant died off.

I think I was just too late with getting these plants going. I live in northern England, so the growing season is quite short.

I believe I need to get these going really early to stand any chance of success.

Plans For Next Year

Start my seeds really early indoors and grow on until they are quite large and then move them into the greenhouse.

I will also be pollinating by hand using a paintbrush to improve pollination rates.

Hopefully, this will lead to a successful crop. Why not sign up for my newsletter to see how I get on?

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