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Zea mays

Sustainable Ewe favourites:

Honey and Pearl,  Painted Mountain,  Blue Hopi,  Supersweet


Quick Reference

Optimum Soil Temperature 20-25
Days to Germination 10-14
Days to Harvest 90-110
Direct Sow or Transplant Direct
Distance Apart 30-50cm
Soil pH 5.5-7.0
Annual/Biennial /Perennial  Annual


A member of the grass family (Poaceae)

Maize, as corn was first known, is an Indian word meaning “giver of life” or “sacred mother” and was domesticated around 6000-10000 years ago in South America.  It was introduced to Europe by Christopher Columbus.

Corn was hand picked up until 1930 when the first mechanical harvester was invented by the Gleaner Harvester Corporation in Independence, Missouri.

There are Four Main Types of Corn:

Flint:  Also known as Indian Corn or Calico Corn.  It has a hard outer shell and generally very colourful kernels.  This is used to make flour, or grits.

Dent:  Also know as Field Corn is grown primarily for cattle feed.

Popcorn:  Grown specifically for it’s ability to pop as the moisture inside the kernel expands.  (However this cannot be popped from fresh as it contains too much moisture.  Dry for a few months before popping)

Sweet Corn:  Is the corn we know best, Fresh on the cob, slathered in butter, this is the corn that is eaten.


As corn is wind pollinated and can cross pollinate it is a good idea to only grow one variety of corn at once, unless you can leave a distance of 2-3 kms between varieties.  Planting in blocks rather than rows to assist in pollination and ensure a good yield.  A sure sign of poor pollination is corn that is missing kernels on the cob when it is harvested.  

Heat and sun loving, plant after frosts in a spot that has all day sun.

While wind is required to pollinate, like everything, too much of a good thing can be bad!  Protect from high winds or consider staking.

Staggering plantings of corn will ensure a steady supply over summer.

Corn is a hungry crop, it likes plenty of Nitrogen and plenty of water.  Thus it makes sense to plant beans with corn as beans will fix Nitrogen.  (see The Three Sisters planting method)

Corn is ready to harvest when the ear attains an angle (around 45 degrees) away from the stalk and the tassels at the end have died off and turned brown.  If in doubt, carefully peel back the husk of one ear and pierce a kernel with your fingernail, the juice should be a milky colour when ripe.

Storing harvested corn:  Corn will not ripen after harvesting so ensure it is ready to be picked.  The sugars in corn will convert to starches within hours of picking so it is a good idea to either eat it super fresh or store direct from garden to avoid loss of sweetness.  In the fridge it will keep up to 10 days.  Corn can be frozen whole (I freeze corn still in it’s husks), or kernels can be sliced off, blanched and then frozen.  It is also able to be dried or canned.  Flint corn can be stored on the cob (it makes and awesome display), or removed from the cob and stored in air tight containers – either as whole kernels or ground.

Seed Saving:  Ensure adequate distance between varieties to avoid cross pollination.  100 plants will ensure genetic diversity.  Seed is mature 6-8 weeks past eating stage.  The average seed life is 6 years.


Feeding:  Start with plenty of organic material and manure, corn loves nitrogen, so plant with nitrogen fixing plants or add Nitrogen to the soil.  Water well to ensure plump juicy kernels.

Fun Facts

Corn is made up of 62% starch, 3.8% oil, 15% moisture, 19.2% protein and fiber.  There are 86 calories per 100 grams

Corn is used in the production of almost everything:  from varnish and paint, fireworks, window cleaner, toothpaste and soap and of course food, including Coca Cola and Pepsi.  In fact more commercial products are sweetened with corn syrup than with sugar

Worldwide production of corn surpasses rice or wheat.  It is grown more widely in Africa than any other crop.

Americas produce around 36.5% of all corn and they consume one third of all corn produced in the world.

Each corn tassel produces around 5 million grains of pollen.

The Corn Palace is located in Mitchell, South Dakota

Fresh corn loosed 40% of its sugar in only 6 hours at room temperature

Once acre of corn eliminates 8 tons of Carbon Dioxide.

Approximately 20% of the worlds food calories comes from corn

Produced on every continent except Antarctica

There are always an even number of rows on an ear of corn and on average has 800 kernels of corn arranged in 16 rows

Depending on the variety the average height of corn is between 2.5-3 meters tall.  The highest on record is over 10 meters.


Smut – Galls form on cob, Destroy infected plants
Tough Kernels – over mature when harvested. Stored too long. Overcooked. Eat fresh
Poorly filled cob – Poor pollination. Block plant rather than in rows.


Corn ear worm – Leaves and tassel eaten. Cobs eaten from the end

Birds love digging up seeds or young seedlings, so protect with netting while establishing your crop..

Possums, rats and mice love corn so keep an eye on your crop or consider installing a cat.

Companion Planting

Beans, Broad Beans, Bush Beans, Climbing Beans, Cucumber, Marjoram, Parsnip, Potatoes, Pumpkins, Radish, Zucchini