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 21°C and 35°C. (Show °F/in)
  • Space plants: 60 - 75 cm apart
  • Harvest in 12-17 weeks.
  • Compatible with (can grow beside): Sweetcorn, Sunflowers
  • Avoid growing close to: Potatoes

Your comments and tips

23 Aug 21, Megan (New Zealand - temperate climate)
Yes. We have grown them for the last two years. If you have a hot, sheltered spot that other plants wither and die in watermelon will thrive. We find it needs good, deep soil and lots of water. Better to go with a few plants a nip off the end once you have a couple of fruit on each rather than try and make one plant produce heaps of fruit.
03 Jan 21, EMC (New Zealand - temperate climate)
Anyone have tips if watermelon would work down in Invercargill? Would love to grow some fruits down here, but can't be tree based types. Rather tight on funds so cheaper is always better, but also happy for advice as well.
05 Jan 21, A (New Zealand - temperate climate)
EMC it is there at the top of the watermelon page for NZ temperate climates when to plant. They grow along the ground and buy some seeds from a seed selling website or shop selling seeds.
11 Mar 20, Sandra (New Zealand - temperate climate)
Help, I planted some watermelon seeds and they have grown so well. Sadly there 13 plants that are so close together in the same pot, I now to worried if I move and replant them they will die. What should I do!
11 Mar 20, Anon (New Zealand - sub-tropical climate)
Take the time to read how to grow things, like how far between plants, between rows, then plant seeds/seedlings accordingly. There is a reason for that, it gives the plant enough soil area to draw the nutrients to grow. The best time to transplant is when the plant is at about the 4-6 new leaf stage or in some cases about 4-6 weeks after germination. The longer you leave it the bigger the transplant shock or death. You be the judge.
26 Dec 19, Phoebe (New Zealand - temperate climate)
I have a watermelon growing and setting teeny baby fruit but they all wither and drop off within a week of setting. Any ideas?
30 Dec 19, anon (New Zealand - sub-tropical climate)
Sounds like you have no bees to pollinate the female flower. Do it by hand. (With a soft artist's brush or use a male flower)
15 Dec 19, Puiti (New Zealand - temperate climate)
Can I grow watermelon in Te Kuiti?
17 Dec 19, Liz (New Zealand - temperate climate)
You should be able to grow watermelon, if you start them early in pots or trays undercover. Have a look here www.gardenate.com/plant/Watermelon
16 Mar 19, alastair (New Zealand - temperate climate)
I am going to try growing them in a glasshouse with heated soil . Are there any varieties more suited to this approach?
Showing 11 - 20 of 44 comments

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.

- John

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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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