Growing Zucchini, also Courgette/Marrow, Summer squash

Cucurbita pepo : Cucurbitaceae / the gourd family

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

(Best months for growing Zucchini in Australia - sub-tropical 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: 50 - 90 cm apart
  • Harvest in 6-9 weeks. Cut the fruit often to keep producing.
  • Compatible with (can grow beside): Corn, beans, nasturtiums, parsley, Silverbeet, Tomatoes
  • Avoid growing close to: Potatoes

Your comments and tips

07 Oct 19, anon (Australia - sub-tropical climate)
Go on the net and look for a natural spray - usually soapy water mixed with other things. Probably you have some grubs.
30 Jul 19, Peter (Australia - tropical climate)
Hi, Can someone recommend a successful Zucchini variety for a hot tropical area such as Katherine, Northern Territory? Thanks
21 Jun 20, Josh (Australia - sub-tropical climate)
TryTromboncino, does amazingly well in a humid SE qld summer where others rot.
31 Jul 19, (Australia - tropical climate)
It is more about planting it the right time. Grab a packet and give it a go.
14 Jul 19, Jack (Australia - sub-tropical climate)
What would you suggest around Brisbane in regard to spacing the plant?
16 Jul 19, (Australia - sub-tropical climate)
Good rich soil 900mm - poor soil 600mm.
17 Jun 19, joe graham (Australia - temperate climate)
as with my egg plant my zucchinis are still producing most times 3 from each plant every 3 days'they are the blackjack variety. the seed was planted first week of December. whats happening is climate change causing this to happen. its middle of June temperate climate is it normal. thanks for any advice
08 Feb 19, Alana (Australia - cool/mountain climate)
Hi, i have big healthy plants buth but the fruit are turning yellow and shrivelling. Ive harvested 6 out of around 20 ive had to throw away. Ived been trying hand pollinating but it seems to make very little difference. Are there any other issues that could be causing this?
10 Feb 19, Mike (Australia - sub-tropical climate)
Read up about pollination - it could be some disease - I have no idea.
11 Jan 19, paul stanley wood (Australia - sub-tropical climate)
try natural spray a mix of onion garlic boil cool strain and spray that easy
Showing 31 - 40 of 255 comments

Hi Gurinder, that’s a lot of zucchinis you have…3000 plants. Based on about 10,000 plants per hectare, this is a sizable area. I do think you should seriously consider seeking serious professional advice. You may have just gone thru a period of extreme weather - heat wise or rain wise, which could have adversely affected fruit setting. Some varieties are more susceptible to this depending on whether they are open pollinated or parthenocarpic hybrids (you didn’t mention the variety so I’m only assuming this stage). So, my suggestion is just to hang in there at this stage and just harvest what you can from the plants. Re fertilizing, this is not an easy question. Ideally you would have had a soil analysis to establish a pre-plant fertilizer (NP&K) and a side-dressing fertilizing (N&K only) program, confirmed by a couple (at least one) leaf tissue analysis about first flowering and maybe half way thru the fruiting season. In lieu of all this you could have given a basal pre-plant dressing of 800-1200 kg/ha of low analysis 5:5:5 or 300-400 kg/ha of high analysis 14:14:14 fertlizer, (or something close to this NPK ratio); followed up by side dressings from first flowering with fertilizers containing only nitrogen and potash (no phosphate). Some growers alternate light dressings (30-40 kg/ha) potassium and calcium nitrate every few weeks from fist flowering. Too much nitrogen early encourages excessive foliage growth and an over-abundance of non-productive male flowers. If you did not give a good pre-plant basal dressing then I would suggest light side dressings every couple of weeks (followed by good watering) with a high analysis fertilizer, something approx to a 14:14:14 fertilizer. I hope this helps a bit. John

- John BEE

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.