Growing Watermelon

Cucurbitaceae c. lanatus : Cucurbitaceae / the gourd family

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

(Best months for growing Watermelon in USA - Zone 7a 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
  • 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 Aug 22, Catherine E Villarreal (USA - Zone 10b climate)
When can I plant seedless watermelon seeds in zone 10b
04 Sep 22, (USA - Zone 10b climate)
March or Aug Sept
02 Aug 22, rhonda (USA - Zone 9a climate)
It is now the beginning of August 2022 and I was wondering if it is possible to grow watermelons from seed in grow zone 9a (Houston Texas) if I grow them in a giant pot and keep it in a shady area of my yard out of the extreme heat we are experiencxing now in Texas? I planted some seeds (direct seeded into the top of a compost pile I have in direct sunlight) they did germinate into very small seedling plants, but because the weather was hitting over 100 degrees they immediately died back. So I am attempting to grow some in a large pot and keeping them out of direct sunlight and seeing if they will continue growing, if so I will try to grow them vertically on a trellis. Has anyone else ever attempted such a experiment? If so, were they successful in getting a watermelon to grow out of season?
13 Jun 22, Fifita Filipe (New Zealand - temperate climate)
Will the seed collected from hybrid watermelon can be ok to grow in our garden???
24 Aug 22, Richard (New Zealand - temperate climate)
It will grow but will not be true to type. You don't know what you will get. Hybrids are produced by pollinating specific flowers with specific pollen. So when the hybrid grows fruit it is neither of these. It is a mix of both, just like our children. If we plant seeds from that fruit we have broken the hybrid chain. The result will be a lottery
17 Jun 22, (New Zealand - sub-tropical climate)
Hybrid is a cross of different varieties - plant these seeds and the watermelons may be hybrid or like one of the crosses.
15 Jun 22, Liz (New Zealand - sub-tropical climate)
Seeds saved from hybrids don't usually grow true.
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
Showing 1 - 10 of 307 comments

Maybe adding eggshells to the soil will help

- Sarah

Please provide your email address if you are hoping for a reply


All comments are reviewed before displaying on the site, so your posting will not appear immediately

Gardenate App

Put Gardenate in your pocket. Get our app for iPhone, iPad or Android to add your own plants and record your plantings and harvests

Planting Reminders

Join our 60,000+ gardeners who already use Gardenate and subscribe to the free Gardenate planting reminders email newsletter.


Home | Vegetables and herbs to plant | Climate zones | About Gardenate | Contact us | Privacy Policy

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.
We cannot help if you are overrun by giant slugs.