The Wonderful World of Traditional Corns

When, at one of our food-garden visits, Sally James told me what she uses her garden for, I was immediately interested.  I asked her whether she would like to write about it on our blog.  Here is Sally's article that could have had the title 'How Corn Became My Hobby'.

There is much more to corn than yellow sweet corn-on-the-cob.

Two years ago, I came across a book written by an American gardener, Carol Deppe [1], on the subject of sustainable agriculture and self-reliance, in which she advocates corn as an excellent crop for the small-scale production of a variety of nutritious wholegrain products in the home kitchen. It soon became clear that she was not talking about yellow sweet corn, but rather a whole range of traditional corn varieties (also called ‘field corns’ or ‘Indian corns’) that are left to dry on the plant and are harvested at the end of the season as a hard, storable grain.

Traditional corns come in many different colours: yellow, of course, but also white, black, blue, lavender, pink, purple, red, brown, bronze, and tan – even green! The inner bulk of the corn kernel (the part that forms the white portion of pop-corn) is called the starchy endosperm, and this can be soft and floury (in flour corn) or hard and see-through (in flint corn). Corn varieties with fairly even amounts of flint and flour endosperm form kernels with a characteristic pit or dent (dent corn). Each kernel type is suited to different preparation and cooking methods.

The familiar sweet corn is actually a mutated flint corn, with an altered endosperm formation that makes it retain sugar rather than forming starch in the normal way. 

Popcorn is a flint corn with a very tough outer layer; as it heats, pressure builds up inside until it explodes open. 

This huge range in corn varieties results from the plant-breeding skills of the Native American people who, over six thousand years and many generations, nurtured a marginal tall grass into the incredibly versatile, useful, and convenient crop known today as Zea mays. Corn has evolved with the communities of people who have shaped it to suit their climates, agriculture, and cooking methods. 

In her book, Carol Deppe provides advice and recipes describing the various ways in which a harvest of traditional corn can be prepared and eaten. Whole kernels of some corn varieties can be popped or parched to make a long-lasting, crunchy treat, while other varieties are well suited to grinding into cornmeal to make various breads, cakes, or porridge (polenta). Believe me, by the time I had read through the recipes I was keen to try growing traditional corn to make some of these delicious-sounding foods for myself.

This is where I ran into a big obstacle: I couldn’t find traditional corn seed in Tasmania, and I couldn’t order it from America. There are two layers of quarantine that block the importation of corn seed into Tasmania: one for the whole of Australia and another between Tasmania and mainland Australia. It quickly became apparent that it would take far more time and effort than I could possibly afford to even try and satisfy these requirements. 

The whole idea nearly stopped there, however after much asking around and some help from Steve Solomon (author of “Growing Vegetables South of Australia” [2]), David Kenyon (Inspirations Garden Centre), and Dr Bob Reid (Cressy Agricultural Research Station), I finally acquired some small samples of traditional corn seeds of varieties that were much closer to what I was after, including 25 seeds of the multi-coloured Painted Mountain dent corn. 

At last some progress had been made, however I was still only part way there. To make most of Carol Deppe’s recipes I wanted true flint and flour varieties, with single-coloured cobs of white or red/tan. It was at this point that I made a decision that was to lead to a major hobby and cement my reputation in the neighbourhood as an eccentric gardener: I decided to try my hand at corn-breeding. 

Corn is a monoecious plant, meaning it has separate male and female flowers. This makes it fairly simple to control which plants cross-pollinate by hand. The male flowers are in the tassel at the top of the plant. The female flowers are lined up in rows, deep inside the husks that emerge from the base of one or more of the mature corn leaves. Each flower is a potential corn kernel. About a week after the tassel begins to shed pollen, fine, thread-like silks start to emerge from the top of the husk leaves, like a crazy hair style. Each silk originates from a separate female flower, and it will keep growing until a pollen grain lands on its surface, grows down into the flower, and fertilises it.

To hand-pollinate corn, you need to cover the developing husks before the silks emerge to prevent random pollination (I tie on a closed envelope, with one of its short ends cut open). You then collect pollen from the tassel of your selected plant by tapping it out onto a sheet of white A4 paper. The pollen is then brushed onto the silks of a second plant, and the husk re-covered. 

In the first year, I converted a large part of our front lawn into a corn-patch (see photo below), and sowed it with a mix of different corn varieties, each of which was known to produce kernels with at least one of the characteristics I was aiming for, such as true flint or flour endosperm, or red-tinted kernels.

As the plants grew, they generated quite a bit of interest from passers-by who had never seen such a varied bunch of corn plants; knee-high, giant, bush-form, single-stemmed, with different husk and tassel forms, and even some with purple streaks in their stems and leaves. Things became even more exciting at harvest time. Because they were grain varieties, I had to wait until the husks had mostly dried out before harvesting, and I had a hard time resisting the temptation to pull open bits of the husk to get a sneak preview of what the cob would look like (not a good thing to do, as it gives pests easy access to the kernels). 

I was not disappointed. My first harvest included many different-patterned cobs, as in the sample shown below:

At the start of the second year of my experiments I planted seed selected for flint or flour endosperm, and single-coloured cobs of white or red/tan. I once again used hand-pollination to control the crosses. At the second harvest, I was pleased to find that some of the cobs were significantly closer to what I was aiming for.

The image below shows some of my red-toned cobs from the first harvest on the left, and some from the second harvest on the right.

This year I have planted out my third corn patch, and am eagerly awaiting the third harvest in the early autumn. Will I succeed in combining red and white single-coloured cobs with consistent flint or flour-type kernels? Only time will tell. 

On the face of it, the time and effort that I have put into this corn-breeding project is kind of crazy. Here I am, two years on, and I haven’t actually arrived at the point of cooking any of the recipes that initially sparked my interest: I’ve never had enough seed of the correct type, and what I do have is far too precious to eat! Why bother? 

I think it’s because once I got going, the process of working on this project became so interesting and enjoyable that it was enough motivation in itself. It’s also really fun to talk about with fellow gardening-enthusiasts (although I wouldn’t recommend this as a safe topic for social occasion small-talk. I have learned to look out for that glazed look that tells me that not everyone finds this as truly enthralling as I do). Finally, I think it is worthwhile to have people here and there who actively grow and improve these traditional corn (and other food-crop) varieties. In this way we can become custodians of a small part of this priceless gift that we have inherited from the generations that came before us. 

For a much more detailed description of the principles of corn breeding, and the way I planned and carried out my own cross-pollinations, I wrote an article with the title 'A Corny Tale'.  You can see this article by clicking here.  A pop-up menu above the page-area allows you to print or download the article.

1) Carol Depp. The Resilient Gardener: Food Production and Self-Reliance in Uncertain Times. 2010, Chelsea Green.

2) Steve Solomon. Growing Vegetables South of Australia: Year ‘Round Tasmanian Food Gardening. 2006, Published by Steve Solomon.