Growing Watermelon

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

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

S = Plant undercover in seed trays T = Plant out (transplant) seedlings

  • 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
  • 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

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?
07 Mar 19, Lea (New Zealand - temperate climate)
am in north canterbury, growing watermelon in glasshouse, didnt have success outdoors, but one in glasshouse has 5 melons of different sizes on it so hopeful , one getting quite large
Showing 1 - 10 of 33 comments

Have a go. Probably need plenty of water later. If not very successful, plant earlier next year - early Sept.

- Mike

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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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