Growing Watermelon

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

(Best months for growing Watermelon in USA - Zone 5a regions)

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
  • 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

08 Jun 22, Marlow (USA - Zone 9a climate)
I seem to have bottom rot on my watermelons. Two out of 3 are effected. I've read that it's because the soil is lacking calcium. I'll be getting a soil tester tomorrow to check the pH. What would be the best thing to add calcium to the soil? I just don't know if that would work or if I should start new seeds and plant in an area that already has the pH suitable for watermelons...
17 Jun 22, (USA - Zone 4a climate)
Probably too late now but use Epsom Salts - scatter some of this in your soil in future especially where you plant the seeds.
13 Jun 22, Sarah (USA - Zone 9b climate)
Maybe adding eggshells to the soil will help
26 Apr 22, Noelle (USA - Zone 10a climate)
Spacing for vertical watermelon growing? I have a 2x4 bed and planted watermelon on opposite ends on one side (Sugar Baby variety) and one on the center on the opposite side (Crimson) with the goal of having them grow vertically. I only expected three plants total but planted more seeds since these were older seeds. I now have eight watermelon plants that are growing beautifully. I don't want to thin, but I'm sure it's necessary. Any advice on spacing for vertical growth? I've read all sorts of different suggestions online.
09 Mar 22, Trish Deeter (USA - Zone 10b climate)
What are the best seeds to purchase for Zone 10b, Costa Mesa, Southern part of California near the ocean?
04 Sep 21, Harrison Brown (USA - Zone 10b climate)
I would like to know what type of fertilizers I can use to fertilizer my pigeon peas, corn, and watermelon plants?
07 Sep 21, (USA - Zone 4a climate)
A general garden fertiliser will do.
21 Aug 21, Sandra Carlton (USA - Zone 8b climate)
I have watermelon plants all over the garden lots of blooms but no fruit yet, they were planted mid July. In zone 8
23 Aug 21, Rosemary McElroy (USA - Zone 10a climate)
I wouldn’t worry unless the blooms drop. Did you plant them as plants or seeds?
07 Aug 21, Sandra Carlton (USA - Zone 8b climate)
How long does it take for watermelons planted in mid July in zone 8 to make watermelons?
Showing 1 - 10 of 31 comments

I am wondering what watermelon will grow in zone 10 (the coastal portion) Thank you.

- Cathy Mallen

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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. Gardenate 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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