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
T                     T

(Best months for growing Zucchini in New Zealand - cool/mountain regions)

  • S = Plant undercover in seed trays
  • T = Plant out (transplant) seedlings
  • 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

09 Oct 19, Sue (New Zealand - temperate climate)
Is there any way to tell which direction a courgette plant will grow in when planting a seedling - they tend to sprawl in one direction and its always a punt which way that will be. Sometimes they end up growing into other plants. My plant has 3 leaves on it and a smaller one coming similar to the one in your photo top of page. Thanks.
14 Oct 19, anon (New Zealand - sub-tropical climate)
Happens quite a bit here. The wind will blow the plant over, so that is the direction it grows in mainly.
15 Jan 19, Julie Sutherland (New Zealand - temperate climate)
We planted a yellow courgette and it is producing courgettes however they are white and not yellow - every other year we have had no problems....why might this be happening?
18 Jan 19, Julie Sutherland (New Zealand - temperate climate)
We planted an actual plant from the nursery... never ever had an issue before nd the people at the nursery assured me they do not have white courgettes....we were wondering if it was a climate thing or maybe a soil issue of deficiency...
25 Jan 19, Mike (New Zealand - sub-tropical climate)
If it is a hybrid it might be a throw back to a parent.
16 Jan 19, Mike Logan (New Zealand - sub-tropical climate)
Are they from the same packet as last year? Could be a mix up of seeds in the packet. I ordered boy choy last year and received Chinese cabbage.
21 Dec 18, Quent (New Zealand - temperate climate)
Do courgettes need trimed like tomatoe plants?
02 Jan 19, Mem (New Zealand - temperate climate)
Its a good idea to trim and leaves that are showing signs of powdery mildew (powdery white spots) or damaged leaves,other than that its not needed.
24 Dec 18, Mike (New Zealand - sub-tropical climate)
They are a vine so let them spread out or up a trellis. Tomatoes are a tree and don't have to be trimmed.
17 Dec 18, Laraine wright (New Zealand - sub-tropical climate)
If a courgettes grows into a marrow when is it ready to pick.
Showing 11 - 20 of 61 comments

I agree with John. For powdery mildew prevention and control I use a brew of 3tablespoons of baking (bicarb) soda, 1/2 teaspoon non detergent dish soap to 6litre of water. The soda changes the ph and destroys the spores, soap acts as sticking agent. MUST test spay, leave 24-48hrs observe for chemical damage. May need less soda. Do not add anything to brew like fertiliser or neem oil, as this will change the ph and the brew will either become ineffective or cause damage. When ok with mix, spray everything (plant, container, soil, stakes etc) all over. Give sprayer a good shake prior and during application. Don't pour leftover brew into soil - ph change can cause growth problems of young plants. I do this weekly from planting out regardless of need; this minimises powdery mildew starting up. My cucs, courgettes and toms get this treatment but the amount of soda required may vary. I keep a note of the brew(s) and results for future reference. Best done in the evening so it has time to do its thing overnight without the risk of sunburn. Make a fresh batch of brew for each spray session. Remove some additional leaves to enable good ventilation throughout plant. What variety of triphid are you growing?

- Karen

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