Growing Watermelon

Cucurbitaceae c. lanatus : Cucurbitaceae / the gourd family

Jan F M A M J J A S O N Dec
                S S S S
T                   T T
                    P P

(Best months for growing Watermelon in New Zealand - cool/mountain regions)

  • S = Plant undercover in seed trays
  • T = Plant out (transplant) seedlings
  • P = Sow seed
  • Grow in seed trays, and plant out in 4-6 weeks. Sow seed at a depth approximately three times the diameter of the seed. Best planted at soil temperatures between 70°F and 95°F. (Show °C/cm)
  • Space plants: 24 - 30 inches apart
  • Harvest in 12-17 weeks.
  • Compatible with (can grow beside): Sweetcorn, Sunflowers
  • Avoid growing close to: Potatoes
  • Mature watermelon
  • Melon flower
  • Watermelon

Large, round or oval, smooth green skinned, delicious, sweet pink fleshed melon.

Some have stripes on the skin.

Some varieties will produce fruit up to 14 kg (31 US pounds).

Harvest when the part in contact with the ground is turning yellow and the fruit sounds hollow when tapped.

Watermelon needs plenty of room to grow as it sends out long vines

Needs a long warm season to mature.

Culinary hints - cooking and eating Watermelon

Cut up and eat in slices.
Use to make fruit drinks.
Use in fruit salads.

Your comments and tips

09 Jul 10, Natalie (New Zealand - sub-tropical climate)
If the melon is a non hybrid I don't think you would have any problems. I would buy a melon from an organic grocer, would then hopefully be not a hybrid. Dry the seeds out before planting. Plant where you want it to grow. And cross fingers. Would love to hear if you have any success. I have grown melons from seeds - they just seem to pop up out of the compost. So don't see why it wouldn't work, but you never know.
16 Jan 17, (New Zealand - temperate climate)
Can anyone give details of how to prune runners/vines of watermelons to achieve better fruit in Canterbury? I was told quite a few years ago that this is a good method in colder climates to encourage better fruit and good ripening.
20 Jan 17, John (Australia - temperate climate)
Probably the best thing to do is to buy heritage seeds that have been listed as originating in short season climates like Canada and the northern USA. They have a much shorter growing season. The other alternative is to wait until 2 or maybe 3 melons have formed and then cut all subsequent runners off to give the plant the most to put into those 2 or 3 melons. Trust this helps.
26 Nov 17, Jilly (New Zealand - temperate climate)
I would.like to know why lately a lot of supermarket watermelons are rubbery and soft in texture?? ..ugly to eat..not lovely and crisp
29 Nov 17, Toni (New Zealand - temperate climate)
Has anyone growen watermelons in Wellington?
28 Dec 17, Uta (New Zealand - temperate climate)
I'm growing them for the first time, in Manawatu. So far with the heat and sun we've been having they're doing well. But they'll need a long season, so fingers crossed. My first transplant died in the wind, so shelter is important, in Wellington too :-)
26 Jan 18, Sally (New Zealand - temperate climate)
I’m in the Manawatu also and have 5 watermelons on my plant, never had success before, it’s been so hot that I’m thrilled to have fruit!! Hope yours have been a success too.
22 Feb 19, Ane (New Zealand - temperate climate)
I'm in Manawatu as well and have 2 plants growing, each have about 6-8 melons. A couple of them are almost the size of a netball and the rest are slightly larger then a tennis ball. Fingers crossed they keep growing:)
30 Apr 18, Sandy (New Zealand - sub-tropical climate)
I sowed my watermelon in mid summer and it's still growing. I'm wondering if it will actually fruit in Auckland this time of year. Should I leave it or remove and try again next summer?
08 May 18, Andrea (New Zealand - temperate climate)
It's frustrating, because the growth is promising, but it won't ripen any fruit that form in the cold weather. Rip it out and start again in spring : )
Showing 1 - 10 of 44 comments

If you pick a watermelon early and its greenish, is there any way to ripen it up without throwing out to the chickens

- Cherry

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This planting guide is a general reference intended for home gardeners. We recommend that you take into account your local conditions in making planting decisions. GardenGrow is not a farming or commercial advisory service. For specific advice, please contact your local plant suppliers, gardening groups, or agricultural department. The information on this site is presented in good faith, but we take no responsibility as to the accuracy of the information provided.
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