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

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
10 Nov 19, Krystal (New Zealand - cool/mountain climate)
Hi Lea, I’m in Rangiora. I’ve got some beautiful watermelon seedlings growing. So glad I’ve come across your post as I was going to plant outdoors. How did your watermelon end up going in the glasshouse? Will you grow again?
06 Feb 19, Cherry (New Zealand - temperate climate)
If you pick a watermelon early and its greenish, is there any way to ripen it up without throwing out to the chickens
06 Feb 19, Mike (New Zealand - sub-tropical climate)
Read up about when to pick them.
20 Dec 18, Kams (New Zealand - temperate climate)
Hi there, I am here in Auckland and recently have shifted my watermelon plant to a 15 Litre Pot, one of the prime reason being our ground is full of roots and generally found it difficult in the past 2-3 years for other plants growing. Do you think it is ok to proceed in the pot and can connect vine to multiple stakes? Kindly advice. Thanks
02 Jan 19, Mem (New Zealand - temperate climate)
Hi I grow watermelons and other melons in pots every year,it can certainly be done but the melons won't be as big.You will also need to take care that the soil doesn't dry out,but isn't soaked and to feed often.I add blood and bone,sheep pellets and worm castings to a mix of 50/50 compost and potting mix to the pot,use a curcubit feed once a week and a general liquid feed every 2 weeks.
21 Dec 18, Mike (New Zealand - temperate climate)
Plenty of people might do it but I wouldn't grow such a big plant in a pot full stop, no matter how big the pot. The nutrient and watering required. Think about raised garden beds with something between the ground and the bottom of the bed like wood pallets. Pallets on the ground - then weed matting and shade cloth - then small stones maybe - then garden soil about 5-600mm deep. Probably quite expensive but is probably the best solution. Could start small and add to the size of the bed/s in future years. Otherwise stick to growing small plants in pots.
23 Oct 18, Debra (New Zealand - temperate climate)
wanting to grow melons this year, I am in North Canterbury any hints for success welcome, am I too late to sow seed ?
25 Oct 18, Mike (New Zealand - temperate climate)
Have a go. Probably need plenty of water later. If not very successful, plant earlier next year - early Sept.
22 Oct 18, Tracy smith (New Zealand - temperate climate)
I have done watermelon seeds in September month & they have come up & r doing well so har. When is the best time to plant them in the ground they r about 1 inch high each I have 4 of them
Showing 21 - 30 of 44 comments

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.

- Anon

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