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

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11 Mar 24, Lea (Australia - temperate climate)
How long do they take from seed
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22 Mar 24, Celeste Archer (Australia - temperate climate)
From seed to harvest involves two phases: 1. Germination (from seed to seedling) 2. Days to harvest which is from seedling to harvest. For your seeds to germinate you need proper germination temperatures and some water (and sunlight). The germination temperature and days to germinate varies by variety -- watermelon seeds tend to like VERY warm temps for germination with germination in about 3 days at 30c and about 10 days at 20c. I would factor about 14 days for germination as a general rule of thumb. Days to harvest varies by variety with smaller varieties taking about 60 days and larger varieties taking closer to 90 days. ‘Charleston Gray’ harvests in 85 days, while Little Darling takes 65 to 70 days, Carolina Cross takes 100 days. I think most varieties fall into the 80-90 day category. Overall, I would allow 114 days, provided the conditions are GOOD (close to optimal) for watermelon from seed for most varieties -- and about 85 days for the smaller (smallest varieties) and you're looking at about 120 days for the really LARGE watermelons.
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19 Mar 24, (Australia - sub-tropical climate)
Read the notes here.
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19 Mar 24, (Australia - sub-tropical climate)
Read the notes here.
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10 Feb 24, Rob Taege (New Zealand - sub-tropical climate)
After last year's disappointment of being so wet, this year has had lots of sun hours with intermittent rain. However, a few weeks ago I noticed two watermelon fruits had their skin punctured. I just chucked on them today and now half of my fruit has punctured holes in them. I have a few pukekos in the paddock that come over and pick my unripe tomatoes from the plants. Would they peck at watermelon fruit as well? If not, what other animal or bird would do this and how do I stop them? I'm 100% sure it isn't rats as the holes are punctured not gnawed, Any suggestions, please before I lose my whole crop.
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07 Feb 24, Lawrence Msibi (South Africa - Summer rainfall climate)
Which is best fertilizer to use in Mpumalanga for planting watermelons and when to apply such fertilizers. Furthermore, the pesticides etc when to start spaying my watermelons, Thank you so much.
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02 Jan 24, (Canada - Zone 3b Temperate Warm Summer climate)
May if you are zone 3b
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02 Jan 24, (Canada - Zone 3b Temperate Warm Summer climate)
Plant undercover in seed trays in May and then transplant seedlings in June
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24 Dec 23, Olawale Kelani (Canada - Zone 3b Temperate Warm Summer climate)
Hi, Please, what is the best time to plant watermelon in New Brumswick, Canada? Thank you.
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04 Oct 23, Anonymous (New Zealand - sub-tropical climate)
hi, trying to find seeds for the watermelon known as All Sweet Watermelon.
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Showing 11 - 20 of 350 comments
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Amy, When to pick watermelons is one of life's great mysteries, but there are a few tips to help you out...Tapping on a ripe watermelon give a heavier thud than unripe ones, watch out for a yellowing stem, a yellowing patch on the underside where it touches the soil and also the skin gets a more powdery look to it rather than it's normal glossy sheen. I picked a couple before I started to get it right. Another thing is to leave it then for another wekk after you have picked it so that it can finish ripening. good luck

- Grahame

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