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 16°C and 35°C. (Show °F/in)
  • Space plants: 20 - 30 cm 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

25 Jan 24, Dot (New Zealand - sub-tropical climate)
Is it ok to plant brassica (not celery) after corn, in the same spot?
30 Jan 24, (Australia - sub-tropical climate)
Yes
30 Dec 22, Mark (New Zealand - temperate climate)
We were hit with terrible and unexpected hail last week and because of this some corn plants have tassels early due to the stress. I keep reading everywhere why it’s happened, but NOT what to do next. Anyone experienced this before? Should I leave, pull them up etc?
05 Jan 23, Anonymous (New Zealand - sub-tropical climate)
Depends whether they can pollinate the corn ear.
10 Sep 22, Wayne McClelland (New Zealand - temperate climate)
Q1. Is Corn a Vegetable or Fruit ? To confuse the issue further, Berries have their seeds on the outside, Fruit has the seed on the inside. Q2. I ask this question for the distribution of NPK in the plots. I have Roots (N), Fruit (K), and Leaf (P), the garden has been farrow now for about 3 years so should be pretty good Kind regards Wayne McClelland
14 Sep 22, Anonymous (New Zealand - cool/mountain climate)
Q1 Botanist call it a fruit. - Q 2 Very basically - N is for leaf production/plant growth - P is for root development and K is for flowering and fruit. Each of these help the plant grow in many ways. Google and learn more about how plants grow. Leaving soil fallow for 3 years does not make it fertile. You need to add manures compost fertilisers etc to make soil fertile and do this 1-2 mths before planting crops.
14 Feb 22, Julia (New Zealand - temperate climate)
Hello I planted corn glass gem and because I had a few gaps in the plot I planted about half again with sweet corn. It has been 15 weeks since planting on 25oct and they are tall but the cobs and not cobbing very much. They seem immature. Is this perhaps as I planted the two types?
04 Mar 22, guggerlugs (New Zealand - temperate climate)
When I plant sweetcorn seed I usually plant a few more than needed if you have failures they are readily transplanted then you can fill the gaps, if they all germinate if you leave a bit of space at the edges you can shift them there.Don't plant too many but plant batches about 4 weeks apart if you have the space then you won't get over run with corn my third crop is just forming tassles now as we finish the last few cobs.
22 Feb 22, Anonymous (New Zealand - sub-tropical climate)
Did you over plant the plot? Corn needs to be spaced as the directions say and it needs to be well watered and fertilised. Plants that germinate later than some can be left behind and not grow well, small thin weak.
17 Feb 22, Celeste Archer (Canada - Zone 7b Mild Temperate climate)
I'm not certain - but when I read your post the first thing that came to mind was a Boron deficiency -- corn likes boron the same way that sunflowers like boron. From the net a study of corn and boron results: It was concluded that: (1) a lack of boron can cause blank stalks and barren ears; (2), the supply of available boron must be continuous; and (3), the critical level of boron in the upper leaves appears to be in between 11 to 13 ppm. I suspect you can apply boron the same way you would to sunflowers (though I am not certain)-- from the net for sunflowers: When the plants are 30cm (12) tall, dissolve 5ml (1 tsp) of borax (for boron) in 350 ml (12 fl oz) of water and spread the solution over 5m (15′) of row. Be careful not to over-apply this solution.
Showing 1 - 10 of 23 comments

Ask a question or post a comment or advice about Sweet corn

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 GardenGrow 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 GardenGrow and subscribe to the free GardenGrow planting reminders email newsletter.


Home | Vegetables and herbs to plant | Climate zones | About GardenGrow | 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. 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.
We cannot help if you are overrun by giant slugs.