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Growing Sweet corn, also maize

(Zea mays, var. rugosa)

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
P P             P P P P

(Best months for planting Sweet corn in New Zealand - temperate regions)


September: sow after risk of frost

  • Harvest in 80-100 days
  • Sow in garden. Sow seed at a depth approximately three times the diameter of the seed.
  • Best planted at soil temperatures between 16°C and 35°C.
  • Space plants: 20-30cm

Frost tender Plant in 4 by 4 blocks to encourage germination Pick when the silky threads on the cobs turn brown or black. Part the top of the leaves and test for ripeness by pressing a grain with your fingernail. If it is milky, it is ready.

Early varieties ripen quickly and are sweeter when just picked.

Avoid planting coloured maize ( for drying) near sweetcorn as they will cross-pollinate and spoil the cobs on both.

Culinary hints - cooking and eating Sweet corn

Pick and cook within an hour. Remove the silks and outer leaves.
Best flavour if microwave about 4 minutes per cob.
Can be barbequed wrapped in foil
Cook large amounts in a stock pot until test soft.
Sprinkle with black pepper and dip in butter.

Your comments and tips

12 Aug 09 Chas (New Zealand - sub-tropical climate)
When cooking sweet corn always leave the leaves on especially if you are to microwave them. Taste the difference.
18 Nov 09 Brenda Morrow (New Zealand - cool/mountain climate)
I wanted to know when do you harvest corn in new zealand
16 Jan 10 Denise Isaac (New Zealand - temperate climate)
Hi its the first time I have grown sweetcorn and so far so good. What sort of pests are there to sweetcorn, I have these little insects on the plants that are fluffy. What is the pest spray to use. Thanks
17 Jan 10 Liz (New Zealand - sub-tropical climate)
Denise, they sound like vine hoppers. The best information I have found on-line is this site www.bonsaiforbeginners.com/passionvine_hopper.html
12 Mar 10 Nanette Baber (New Zealand - sub-tropical climate)
I am a beginner. I started growing my corn mid February. My cobs are just starting to grow but my leaves are already spotty gold-ish brown not green. Does that mean I have pests/diseases on my corn trees?
13 Mar 10 Jacqui (New Zealand - temperate climate)
Hi there - my father has grown lovely sweetcorn this year however lately some of the kernels are a bit shrivelled looking and a different colour to the rest. Doens't seem to affect the flavour. He thinks it might be sucking bugs or the lack of rain - any ideas or remedies? Thanks
20 Dec 10 Dennis Hourigan (New Zealand - temperate climate)
last summer all the silk was eaten off the cobs on our plants and they didnt mature. any ideas?
09 Jan 11 Tina (New Zealand - sub-tropical climate)
First time gardner and corn plants have grown really tall but can't seem to see where the corn grows from?? I planted these begining Dec should they have ears yet??
10 Jan 11 Liz (New Zealand - sub-tropical climate)
Dennis, I think your corn was attacked by a caterpillar. Ask your local plant shop for a suitable remedy. Tina, the corn cobs grow from the side of the stem. They should be starting soon. Have a look at our companion site www.gardenate.com, where there are some pictures.
31 Jul 11 Murray (New Zealand - cool/mountain climate)
I have small spare paddock (in the woodville area so it's relatively wet.) and would like to try a maize maze for my friends. Any tips for the best species and planting times?

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See planting calendar for these climate zones

New Zealand - cool/mountain,   New Zealand - sub-tropical,   New Zealand - temperate  

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