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 P          

(Best months for growing Sweet corn in USA - Zone 7a regions)

  • P = Sow seed
  • 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

19 May 22, Mike (USA - Zone 9a climate)
How much 33-0-0 Nitrate should I use on my sweet corn per 100 ft of row? My rows are pretty big, so I would say the corn is at least 2 feet apart from row to row. That said should I plant at the bottom of the rows, or closer to the plants? Thanks.
24 May 22, Anonymous (Australia - sub-tropical climate)
Is the 33-0-0 the NPK of the fertiliser? If so I would use a more balanced fertiliser 12-15N, 3-6P, 8-15K. Grow your corn to about 1.5 feet and then run a handfull down each side covering about 4-5' with each handfull. Then hill the soil up around the plants - new roots will grow and help stabilise the plants. If you want to fertilise before planting don't use 33N - it will burn the roots of new germinating plants. Spread the fertiliser over about 1' of the row width and rake/dig it into the soil before planting seeds.
18 Mar 22, Elise Blanchard (USA - Zone 7b climate)
Is it too late to plant corn here in zone 7b?
19 Mar 22, Elder (USA - Zone 7b climate)
No, to be safe succession plant. Starting late Feb. thru Mar.
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.
30 Jan 22, Margaret Hefner (USA - Zone 10b climate)
Everything wonderful to you and yours for 2022 and following! Wow, I was getting frustrated to find an endeavor that produced something that I can read, use, understand, not mis-understand... y'all are my new champions (as if champions ever get old). Welcome back, and glad to discover you, Margaret in Baja January 30! I have the whole year to be able to appreciate you!
28 Oct 21, Mike (South Africa - Semi-arid climate)
Can I plant sweet corn on dryland/with rain?
Showing 1 - 10 of 385 comments

No, to be safe succession plant. Starting late Feb. thru Mar.

- Elder

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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. Gardenate 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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