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                  
      T                
      P P P            

(Best months for growing Zucchini 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: 20 - 35 inches 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

05 Jan 11, Kate Moore (Australia - temperate climate)
My zucchi plants grow enormous, flower copiously but then the fruit just shrivells away to nothing. I haven't had one fruit from either plant, despite about 10 flowers at a time per plant. I'm in Cottesloe, WA
29 Jan 11, Tracey (Australia - temperate climate)
An even easier way to hand-pollinate - pick the male flower, pull the petals away leaving the stem and the stamen (the long yellow bit sticking out of the middle of the male flower) and brush the stamen onto the stigma (the thing inside the centre of the bloom) of the female flowers. You can do the same with other cucurbits eg pumpkins, cucummbers. I do mine on the way out of the house in the morning. Cucumbers are a bit harder as the flowers are so much smaller - you might need a paintbrush for those!
09 Jan 11, Amber (Australia - temperate climate)
Me too, Kate! I'm in Trigg and experiencing the exactly the same with my zucchini plants. I was told that my problem is a lack of bees for cross pollination between the male ans female flowers...
25 Jan 11, paul (Australia - temperate climate)
to hand pollinate: get a small soft paint brush, open the male flower gather pollen on brush then open female flower and light coat on the bit inside, you have now pollinated your zuchinni it should only take a couple of days to watch the zuchis grow, amazing!
17 Jan 11, Vera (Australia - temperate climate)
Try watering your zucchini from underneath and don't wet the leaves or plant as this makes them rot
22 Dec 10, trevor west (Australia - temperate climate)
We brought seedlings they have turned out yellow in color and huge?? is there other varieties ?? only know of green and they are smaller thank you..
01 Jan 11, Elizabeth (Australia - temperate climate)
Hi Trevor there are many different varities of Squash/Zucchini's. You might have the Golden one. Pick your Zucchini/Squash often and while the fruit is small rather than really really large, as this will encourage the plant to fruit often, also the fruit won't have large hard seeds inside.
07 Dec 10, gurinder (Australia - sub-tropical climate)
My plants are giving fruit at age of 7 weeks. Should I remove the first fruit? The sizes are very uneven too. What fertilizers I need to use for 3000 plants?
11 Dec 10, John BEE (Australia - temperate climate)
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
21 Aug 14, Olivia (Australia - temperate climate)
Does anyone know where to get parthenocarpic ("self pollinating") zucchini / summer squash seeds in Australia? Thanks for your suggestions in advance!!!
Showing 191 - 200 of 255 comments

I have some zucchini planted alongside a bed of sweet potato and have just read zucchini should not be planted alongside potatoes! The potato bed is secure in a raised bed. Please advise the issues? Regards................

- Phil

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