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

Your comments and tips

23 Oct 18, Mike (New Zealand - temperate climate)
When they have produced a good root system. Wait until they have several leaves. Important to keep as much soil in contact with the roots as possible when planting out. Try and protect them from the sun for the first week. In future plant in a little pot like a 500 gm margarine container with a few holes in the bottom to let water drain out. When they are about 3-4 weeks old plant out. If no frosts you can plant directly into the soil.
11 Oct 18, Jo (New Zealand - temperate climate)
Planted watermelon seeds late last summer,didnt grow. Now they are sprouting but stem red colour after second leaf. Is this normal?
12 Oct 18, Mike (Australia - sub-tropical climate)
Best tasting melons are grown in the spring here. I don't know about the red stem stuff. They will start picking them here in about a months time. I LOVE EM.
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?
17 Sep 18, Mike (New Zealand - temperate climate)
Plant earlier. If no fruit developing when it starts flowering check for bees. Should have fruit developing by 10-12 weeks. Hand pollinate if no bees.
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 : )
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:)
Showing 31 - 40 of 44 comments

It will take approximately 12-17 weeks

- Liz

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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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