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.

Your comments and tips

30 Jun 20, Anonymous (New Zealand - temperate climate)
Corn needs to be planted in rows about 6-800mm apart. Seeds need to be planted about 150mm apart. Best to grow 2 or more rows together in a block for pollination. When the tassel and silks come out it takes about 5 days for pollination. Then about 21 days for cob to be ready to pick. Read up on the net.
04 Feb 21, Helen Tapper (New Zealand - temperate climate)
This is my 2nd season of growing corn, last season was very successful, this year - not so. I have planted them almost exactly in the same spot as last season. Was that the right thing to do or wrong. The other point is that we have had some pretty crazy summer temperatures, high 20's then low to mid teens. I fertilised the garden during the winter/early spring.
05 Feb 21, (Australia - sub-tropical climate)
Better to plant in different spot. Corn is a big user of fertiliser and water. When preparing the soil add compost/manures if possible, Soils always need some fibre replacement each year. Then mark out your rows about 50-60cm apart, Scratch a furrow in the soil and run some fertiliser in the furrow - I use Bunnings rooster booster. Have the soil wet before starting, after planting give another watering. Don't water again for 3-4 days. Too wet seeds will rot. When plants are 45cm high run some more fert down each side of the plants and hill the soil up around the stalk. Corn pollinates for 5 days and you pick it approx 21 days later. I just picked 28 cobs last week. S
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?
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.
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.
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.
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.
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?
Showing 11 - 20 of 23 comments

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