Growing Watermelon

Cucurbitaceae c. lanatus : Cucurbitaceae / the gourd family

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

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

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
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?
01 Mar 19, Lemeze Hartley (South Africa - Summer rainfall climate)
Can watermelon seeds be planted in March as its still very warm in Cape Town
13 Mar 19, Donovan (South Africa - Dry summer sub-tropical climate)
Yes you may but there's a good chance that the seeds will take longer to sprout or not sprout at all. I still think it's worth taking a chance. I'm seeding mine in Saturday and hope for the best.
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.
13 Jan 19, Grahame B (Australia - tropical climate)
Water melons must have been invented for rank amateurs. I live in Coconut Grove, Darwin, NT and have zero gardening experience, but decided to plant some water melon seeds (in pots) at the end of October - build up time to our summer wet season. They germinated fast so out into the garden they went with a lot less ground preparation than there could have been. They grew, started producing flowers (male only for quite some time) so I kept watering them with the odd bit of general purpose soluble plant food. I haven't seen any diseases so they haven't been sprayed - apart from the termite man's overspray with he did my house's annual ant and spider treatment. Then, in early December, growth went up a few notches; I could see how far a vine had grown in a day. They started taking over the garden. Flowers appeared everywhere, as did tiny native bees to attend to pollination. Every few days a small watermelon appeared and quickly got bigger. At that point I sought some advice from a local garden shop on what I should be doing; they told me to keep watering and sold me some organic fertilizer pellets to feed them with. Now they've taken over the garden, have started climbing fences and keep on producing new melons. I'd never have imagined it could be that easy.
09 Dec 19, Linda (Australia - tropical climate)
Hi Grahame, can you tell me what type of seeds you used please where they from a packet or out of a fresh melon? Thanks
13 Jan 19, Mike (Australia - sub-tropical climate)
I have never been able to grow them. I really don't have the ground to do it. Watermelons like virgin soil. There is a lot of difference between a plant growing well and producing a good end crop. I have rock melons growing - huge - some would weigh 3-4 kg. First one I picked, tasteless - probably too much watering. Have cut back the watering. Over watering when the fruit has grown it's full size can make the melons split. Hope it keeps going well for you.
Showing 141 - 150 of 355 comments

Ask a question or post a comment or advice about Watermelon

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 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.