Growing Sweet corn, also corn,maize

Zea mays, var. rugosa : Poaceae / the grass family

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

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

  • P = Sow seed

October: After risk of frost

  • Sow in garden. Sow seed at a depth approximately three times the diameter of the seed. Best planted at soil temperatures between 61°F and 95°F. (Show °C/cm)
  • Space plants: 8 - 12 inches apart
  • Harvest in 11-14 weeks.
  • Compatible with (can grow beside): All beans, cucumber, melons, peas, pumpkin, squash, amaranth
  • Avoid growing close to: Celery.
  • A seedling
  • A young corn plant
  • Feathery cobs on side of stem. Male flowers at top.

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

17 Jan 09, Kiran Kumar M (New Zealand - sub-tropical climate)
Hi my name is Kiran Kumar .M. from india, i am working in Some private company in that i have conducted temperate sweet corn trials and these trials revealed that it can be grown in sandy soils and plants are most susceptable to stem borer attack
09 Sep 09, Liz (New Zealand - temperate climate)
Mike, 4 x 4 blocks means plant in 4 short rows, 4 plants to a row, so that the plants are fairly close together to increase the chance of cross-fertilisation as the pollen is wind blown. Mark, putting 2 seeds in together is because there is a chance that one will fail to grow.
02 Jan 12, Shane Sowerby (New Zealand - temperate climate)
Is there anywhere in New Zealand where I can buy Purple Corn seed?
10 Nov 12, Torben Tilly (New Zealand - temperate climate)
Where can one buy Purple Corn seed in New Zealand?
21 Aug 18, Philip Lim (New Zealand - temperate climate)
I have some purple corn seed if you are looking for some. Let me know your address and i will post some to you.
16 Jul 19, Peter field (New Zealand - temperate climate)
We havnt had a frost up in the far north(kiataia) for zonks. I have wet ground temp of 13 deg . Can i plant corn
17 Jul 19, (New Zealand - temperate climate)
It does say plant from - Sept. Soil temp 16+. We are in July - have a think about it. Do something about trying to dry out your soil. Add decompose compost or manures to aerate the soil - have good loose soil - not heavy wet soil. Corn is a summer - autumn crop so the thing about frost is not important.
28 Jun 20, Judi (New Zealand - temperate climate)
My 6-yr-old came home with an egg carton of sweetcorn seeds he'd planted at school. We put them on the windowsill and they've sprouted beautifully. But it's June, and although it's very mild now (in Waikato) we're expecting to get winter weather soon. He's very excited about these seedlings and would love to grow them to fruition - do you think I could grow them in a large pot as an indoor plant?
28 Jun 20, Liz (New Zealand - temperate climate)
If you can stand your pot near a sunny window, you might be able to keep the sweetcorn growing. Protect it from cold temperatures and make sure it has plenty of light -
29 Jun 20, Anon (New Zealand - temperate climate)
Corn needs full sunlight to produce a good cob. If you fail this time try a more suitable time like spring summer to try again.
Showing 1 - 10 of 23 comments

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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. GardenGrow 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.
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