PlanterTomato Vegetable Gardening

Floriani Red Flint Corn

Last summer, I grew a variety of flint corn called Longfellow.  This variety has long, thin ears and produces a low sugar corn used to make tortillas, corn bread and other dishes that require this type of corn.  A reader of this blog, was kind enough to send me another variety of flint corn to try called Floriani Red.  I had an opportunity to do so earlier this week and would like to recommend it for those interested in growing staple crops in their gardens.

Floriani Red is a relatively rare flint corn that originates from the northern part of Italy.  The corn hulls are a beautiful red color and the grain itself is a deep yellow. I used some of the grain sent me to make pollenta, an Italian side dish that is made from medium-t0-fine ground corn that has been cooked with water and butter.  Floriani corn was cultivated in Italy specifically for pollenta so it's no surprise that it worked wonderfully well for this dish.  The Floriani Red has a rich corn taste and the pollenta was more interesting visually because the red hulls end up as little red flakes in the final dish.  (Pollenta made with yellow corn is uniformly yellow)

Corn is the easiest grains to manage because it only needs to be ground, versus other grains such as wheat or oats that need to be threshed (loosening the grain from the chaff) and winnowed (separating the grain from the chaff) before grinding.

For more information about grinding corn, see my prior post on grain mills and on grinding corn.

If you would like to grow Floriani Red corn, you can purchase seeds from Fedco, Heritage Harvest Seed, and several other suppliers.

Special thanks to Kelley who was kind enough to send me this variety to try.

How To Choose Sweet Corn Varieties

In this posting, I'll describe the historical development of sweet corn and describe various the various categories that are available to home vegetable gardeners.

The History of Sweet Corn

Corn has been cultivated in the Americas for somewhere between 8,000-10,000 years.  For most of that history, the corn grown was high in starch and low in sugar. Generally referred to today as "field corn," this type of starchy corn is traditionally used to make a variety of foods such as corn bread, tortillas, tamales, polenta, and hominy. It is also used as fodder for animals. (For more information about these starchy corn varieties, check out my posting on dent and flint corn)

Sweet corn is a naturally occurring mutation of field corn.  A change in just one gene within the corn plant results in an increase of sugar content from 4% in field corn varieties to over 10% in most modern sweet corn.

There is debate among scholars as to when this mutation occurred, but at least some scholars believe that the first sweet corn mutations occurred over 1,000 years ago in the area around Peru and Bolivia.  Research done by Paul Frederick on the growth of the New England Corn Industry suggests that native Americans in the U.S. also cultivated some sweet corn, but it was not a particularly important crop relative to field corn varieties.  Frederic's explanation for this is that native peoples were less interested in growing sweet corn because it is less hardy than field corn and because the sweetness declines rapidly once the corn has reached maturity, thereby eliminating any flavor advantage of sweet corn over field corn.  In other words, from the perspective of flavor, it reverts to the flavor of field corn so quickly that the trade off in hardiness wasn't worth it.

Photo: Mayan Corn God

According, A. T. Erwin who wrote a book about the history of the canned corn industry, sweet corn as we know it today has it's origins in New England.  Erwin believes that sweet corn was introduced into Plymouth, Massachusetts by the Iroquois in 1779.

Diorama of Iroquois growing corn

Various Types Of Sweet Corn

• Sugary Corn - Sugary, or "SU" corn varieties, were the original sweet corns.  These corn varieties currently have sugar content of 9-16%, a major increase versus field corn that has 4% sugar.  SU corn tends to be hardy, but as mentioned above, it losses its sweetness very quickly once the corn has matured or been picked.  As a result, SU corns need to be consumed immediately upon harvest, or preserved by canning or freezing.  One key advantage of SU varieties is that they are able to germinate in cooler soils, so they may be a good choice for you if you are a Northern gardener.  SU varieties also tend to have the tenderest kernels and some folks claim the most authentic corn taste. Common SU varieties include: Silver Queen, Country Gentleman, Golden Bantam and Jubilee.

Silver Queen

• Sugar Enhanced - Sugar Enhanced, or "SE" corn varieties were developed at the University of Illinois during the 1950's. They have an additional gene that expresses sweetness in corn.   These varieties are 14-35% sugar. Importantly, they retain that sweetness for up to 4 days after harvest or maturity.  This makes SE varieties an excellent choice for home gardeners. One downside is that SE varieties are less tender than their SU cousins. Some well known varieties include: Bodacious, Kandy Korn, Maple Sweet, Tuxedo, and Peaches & Cream.

Peaches & Cream

• Super Sweet - Super Sweet, or "SH2" corn was also developed at the University of Illinois in the 1950's.  Super Sweet varieties have massive sugar content -- 28-44% and they tend to retain this sweetness for an extremely long period of time - up to 10 days after maturity or harvest.  Fans of Super Sweet corn will tell you that kernels are crisp, while detractors view SH2 kernels as tough. Common SH2 varieties include: Illini Gold, How Sweet It Is, and Early Xtra Sweet.

Early Xtra Sweet

• Synergistic - "SY" corn is a hybrid cross between SH2 and SE corn varieties that produces some characteristics of both. Specifically, the tenderness and flavor of SE varieties with the increased sugar content and storage capabilities of SH2 corns.  Some examples include: Montauk, BoJangles, Honey Select, and Applause.

Montauk

• Bt and Round Up Ready - These are sweet corn varieties that are genetically modified for use by commercial agriculture. I am listing these here because GMO's, or genetically modified organisms, are a hot topic in the news these days and because there have been reports that Bt corn may soon be available for sale to consumers at Wal-Mart. Genetically modified corn varieties are ones where an additional gene has been introduced to the plant in order to provide it with resistance to pests, pesticides or herbicides.  In the case of Bt corn, genes from the bacteria Bacillius Thuringiensis are introduced to the corn plant in order to make corn toxic to corn borers, a variety of insect that damages corn crops.  Round Up Ready corn is sweet corn that has been modified with the genes from Agrobacterium Sp. CP4. This gene conveys resistance to the herbicide glyphosate (Round Up).  This allows farmers to spray their fields with Round Up to kill weeds while leaving the Round Up Ready corn plants unharmed.  Kinda like the neutron bomb that kills people but leaves the building intact.

Corn Borer

Other Choices

When you shop for sweet corn for your garden, you will be faced with color and maturity choices that cut across all the groups.  So if you only like white or bi-color varieties you will be able to find some that are SU, SE, SH2 or SY.  The same applies to early and main season varieties.

• Maturity - Early season varieties mature in 65-75 days while main season corn takes 75-100 days depending on variety and your climate.
• Color - Sweet corn comes in yellow, white, bi-color and in rare instances other colors such as blue or red.

Cross Pollination Issues

While not specifically related to particular styles of corn, I want to make you aware of this issue as you plan your garden. Corn is pollinated by the action of the wind taking pollen from the tassels of the plant to the silk on the immature ear.  

As a result, corn crops can easily be cross-pollinated by other varieties if they are planted too close.  Such cross pollination can effect the color of the corn (for example, a white corn variety will produce yellow or bi-color kernels) or the flavor and texture of the corn can be negatively impacted (For example, SH2 varieties that are cross pollinated end up very tough and starchy). 

A general rule of thumb is to separate corn varieties by either time or distance.  If you are growing two varieties, select ones that mature at different times - for example a 70 day variety and a 90 day variety. Tassel formation and pollination will occur at different times, reducing the likelihood of cross pollination between the two varieties. Alternatively, plant different varieties in fields that are 250 feet apart. There will be some cross pollination at this distance, but not sufficient to materially impact the crop.  If you want to completely isolate your corn crop, separate fields by at least 700 feet.

Grinding Your Own Flint or Dent Corn

In this posting, I describe the steps you need to grind home grown flint or dent corn and how to calculate your yield in bushels per acre.

Regular readers of this web site know that I've been experimenting with growing grain in my small suburban backyard.  In September, I harvested my first batch of flint corn.  After removing the kernels from the cob, I had about 8.5 pounds of dried corn seed to convert to corn meal.

Removing the Corn From The Cob

Removing corn from the cob without the use of some sort of sheller is impractical, even for very small quantities of corn.  Hand cranked shellers operate by pulling the cob through a set of teeth that separate the corn from the cob.  These devices range in price from about $30 for a plastic model (doesn't look very durable) to over $230 for a top of the line model offered by Pleasant Hill Grain.  While a good-grade metal hand cranked sheller can be purchased for $80, the price was still a bit high for me given the small quantity of corn I needed to shell (About a grocery bag full of dried and de-husked ears) 

Searching for an alternative solution,  I found a simple $8 hand sheller that worked quite well.  To use it, just place the sheller over the top of the ear and twist the device while pushing down.  The rotation of the teeth within the sheller remove the kernels from the cob.  Using this device, I was able to shell all my corn in about 30 minutes.

Grinding Corn

There are many different styles of grain mills at a range of prices.  For those interested in learning more about various grain mills, please see my prior posting, Grain Mills for Grinding Corn & Other Grains. Since our family already owns a Kitchen Aid stand mixer, I decided to purchase the grain mill attachment for that device.  It proved very serviceable and I would recommend this to anyone who both owns a Kitchen Aid and is processing only small amounts of grain.

To operate the grinder, you remove a small cover on the front of the stand mixer and insert the grain attachment.  Then tighten the attachment screw on the side of the mixer to lock the grain mill in place.  You then load grain into the hopper at the top of the grain mill and turn the mixer on to full power. 

An auger within the mill drives the grain against a rotating grinding stone that converts the grain into meal or flour.  The coarseness of the grind is controlled by an knob on the front of the mill that adjusts the gap between the grinding stone and the auger -- the smaller the distance, the finer the grind.  The Kitchen Aid grain mill let you adjust the the grind in 12 increments.

One caveat.... some reviewers of the Kitchen Aid grain attachment on Amazon.com mention that they damaged their stand mixers by trying to grind the grain from a kernel to flour in one pass.  At their suggestion, I ground my grain in two stages; first doing a coarse grinding and then adjusting the grinding wheel to produce meal at my desired final level of coarseness.  I found this system worked and did not seem to over-tax the machine. 

Below is a photo of corn meal ground at level #1 (most course)

Below is another photo showing the second grinding at level #6.  This produced meal that was on average about about the size of grains of sand.

One more thing to note... while I was very happy with the results I got using the Kitchen Aid attachment, I'd like to point out that that it does not produce meal that is anywhere near as consistent as commercially purchased corn meal.  Most of the meal will be the size of sand but some will be as fine as flour. As a result, the mouth-feel of polenta (an Italian dish made from boiled corn meal) made from my home-ground meal was different than that produced by store-bought corn meal.  I actually prefer the results from the Kitchen Aid, but those expecting an eating experience that is identical to store purchased corn meal may be disappointed.

My Corn Yield

I'm very pleased with the results of my first experiment growing flint corn, particularly since I grew an heirloom variety (Longfellow) that dates back to the time of the Pilgrims. Calculated on a yield per acre basis, I got 107 bushels per acre from my little suburban plot.  For perspective, the average yield per acre on farms in top corn producing states like Iowa and Illinois is 157 and 164 bushels respectively according to a 2004 study by Purdue University.  Importantly, these yields are for modern corn varieties, not heirloom ones like the variety I grew. Yield per acre has increased steadily over the last 80 years due to the introduction of modern varieties; in the 1930's, farms in Indiana produced just 30 bushels per acre on average according to the same Purdue study.

Corn Math

If you decide to grow flint or dent corn, here is the math you'll need to calculate your yield on a per acre basis.

• Bushel - this was once a volumetric measure but has since been converted to weight because of the inconsistency between crops like corn, soybeans, and wheat.  A bushel of corn is now standardized at 56 pounds per bushel without cob, and 70 pounds per bushel with the cob.
• Acre - There are 43,560 square feet in an acre.
• First calculate your yield in bushels by dividing the weight in pounds of your shelled corn by 56.
• Next calculate the acreage by dividing your garden space measured in square feet by 43,560 square feet.
• Finally, divide the results of the two previous calculations. (Your yield in bushels divided by your space in acres) The result will be a bushels per acre measure that you can use to compare to commercial and/or historical yields.

Photo: Longfellow Flint Corn

Flint Corn & Grain Mills Used To Grind Corn, Wheat & Other Grains

In this posting, I'll show some photos of my sweet corn and flint corn and let you know a little about your options to grind flint corn into corn meal.

In a posting last month, Not All Corn is Sweet Corn, I described the types of corn you can grow in your garden (sweet, dent, and flint) and provided basic growing information.  This is my first year growing Flint corn and I'm very pleased with it's progress. 

As the old saying goes, corn should be "knee high by the fourth of July" and mine was.  However, it is now over 9 feet high and I can see tassels forming on the immature ears.  If all goes according to plan, I'll harvest the flint corn at the end of August or early September.

Flint corn is a variety of low sugar corn that is used to make corn bread, polenta and tortillas.  It is left to dry in the field and then ground into meal.

Photo: Old fashioned grist mill located in Sweden

Options To Grind Corn Into Meal

I've been exploring my options for grinding corn and other grains such as wheat, oats and rye and want to let you know what I've learned about the subject.  Here are the main types of grain mills on the market:

Hand Grain Grinders - Hand grain grinders can be less expensive than those that run on electricity and they probably are more durable.  However, it can take 5 minutes to grind just two cups of grain and you'll get a workout in the process.  If you live off the power grid, a hand grinder is your only choice, but for the rest of us, electric is the way to go.  There are three types of grain mills on the market but hand grinders only come in stone and burr varieties. (see below) Manual power does not provide enough speed to drive impact mills.

Electric Grinders - There are several types of electric grinders on the market:

• Stone - This works just like old fashioned water driven grist mills. The grain is ground between two heavy stones.  The bottom stone has grooves in it that become shallower as they radiate from the center of the stone to the outer edge.  When grain is dropped into the mill, it falls into the channels and the rotating top stone progressively grinds the grain into smaller particles as it moves through the narrowing grooves towards the outer edge of the stone. 
  

 

Photo: stone grinding wheels

Stone grain mills are probably the best on the market.  If you plan on grinding lots of grain (from your garden or purchased whole from a health foods store) it's probably worth investing in a stone mill.  A brand that has a good reputation is the Hawo manufactured by Tribest.  There are several models and they cost $400-$600. 

• Burr - work like stone mills but use metal plates instead of stone to do the grinding.  They generally don't grind as finely as stone but they can be a bit little less expensive. 
  

A brand called the Family Grain Mill is made in Germany and has a good reputation.  It is sold as a hand operated device for about $140, but you can add a motorized base if you want to upgrade.  The electric base will set you back another $280.  The Family Grain Mill is probably a good option for those that don't want to invest too much before knowing whether they want to do much grinding.  Go with the manual version and then add the electric base later on. 

• Impact - With impact mills, the grain is pulverized by two metal wheels that have interleaved sets of raised metal plates. There is a small space between the plates and the grain is ground by passing it through these small spaces at very high speed. 
  

Photo: Impact grain mill "stones"

Impact grinders are noisy but they are the least expensive motorized grinders on the market.  They can be purchased for $170-$250 dollars. Nutrimill is a well known brand

Fo Kitchen Aid Mixer Owners

If you have a Kitchen Aid stand mixer, you probably know the company sells a variety of attachments such as a pasta cutter, vegetable shredder and meat grinder.  In addition, Kitchen Aid sell a burr-style grain mill attachment that gets decent reviews and costs about $140.  If you already own a Kitchen Aid mixer and don't know if you are going to be grinding much grain, this is probably an excellent way to get started.  Note: Be sure to buy the right attachment for your model of Kitchen Aid mixer.

Since our family owns a stand mixer, this is what we plan to do.  If we find ourselves grinding more grain (homegrown or store bought) we always have the option to upgrade to one of the more expensive stone models and sell the used Kitchen Aid attachment on eBay.

An immature ear of Longfellow corn

Not All Corn Is Sweet Corn

Every year I grow sweet corn in my garden.  However, this year, I'm also growing a variety of corn that is not meant to be eaten fresh and is not sweet at all.  In this posting, I'll discuss different types of corn that can be grown in the home garden.

Let's face it, homegrown tomatoes and sweet corn are the reason most of us get started in vegetable gardening.   Each year, I grow a variety of sweet corn called Silver Queen.  It's a very popular regional variety that was grown extensively in the mid-Atlantic states.  I won't go into detail about this variety since it is well known.  However, I grow it both for its wonderful flavor and for sentimental reasons. 

My first taste of homegrown sweetcorn was as a teenager.  My father and I visited his friend and fishing buddy Tom Cofield, at his home in Maryland.  Tom and his wife prepared Silver Queen as part of the meal and I probably ate 4 ears that night, forcing the Cofields back into the kitchen to make another batch.  In addition to being a very nice guy, Tom was Outdoor Editor for the Baltimore News, an avid fisherman and hunter, and, with Lefty Krey, co-developer of the "Deceiver," a classic salt water fly lure.  Thanks Tom for introducing me to this wonderful variety.

Not All Corn Is Sweet Corn

While most gardeners grow sweet corn (Zea Saccharata) like Silver Queen, it's also possible to grow other types that are higher in starch and lower in sugar.  These varieties of corn have a sugar content of about 4% versus sweet corn that has a sugar content of about 10%.  Starchy corn varieties are used for making corn meal that goes into dishes such as tortillas, tamales, polenta, and hominy grits.  Actually, there are three types of high starch corn:

1. Flint Corn (Zea Mays Indurata) - has a very hard outer layer and very low moisture content.  It is sometimes referred to as calico corn or India corn and comes in a variety of colors including yellow, red, orange and blue/purple.  Flint corn dates back thousands of years and was the corn eaten by the first colonists at Plymouth Massachusetts.  These first settlers adapted corn to traditional english recipes, replacing oats with corn for porridge or wheat in pancakes.  Corn eaten in this fashion was probably part of the first Thanksgiving meal.
2. Dent Corn (Zea Mays Indentata) - is softer than flint corn and each kernel has a small indentation on the top of the kernel from which it gets its name. (see photo below) Dent corn is generally white or yellow but is used in the same way as flint corn - ground into flour for use in pancakes, bread, etc. 
   
3. Popcorn (Zea Mays Everta) - popcorn is an extreme form of flint corn with a soft starchy center and a very hard exterior.  When the kernel is heated, moisture inside builds up pressure until the kernel explodes.

Photo: Flint corn from Slow Food USA web site.

Photo: From Seeds of Change web site showing SOC Oaxacan Green corn clearly showing the "dent" on the top of the kernel.

Longfellow Flint Corn 

Flint and dent corn can be purchased from a variety of suppliers including Johnny's Selected Seeds, Seeds of Change, Sand Hill Preservation, and Victory Seed.  Varieties of dent corn include: Bloody Butcher, Silver King, Hickory King, and flint corn: Blue Hopi, Dakota White, and Apache.

I'm growing a variety of flint corn called Longfellow.  This variety has golden-orange kernels on a cob that is about 12 inches in length.  It is an heirloom variety from New England and grows to 8 feet in height in approximately 110 days.  Sadly, this venerable old flint corn variety is disappearing rapidly (It's on Slow Foods list of 1,000 unique American seeds, fruits, nuts, livestock and game that are threatened)  I purchased Longfellow seeds 2 years ago from Baker Creek but they no longer offer this variety.  Sand Hill Preservation will also occasionally have it for sale. 

 

Photo: From the Living Crop Museum web site, Wilmington College of Ohio

Growing & Harvesting:

Flint & dent corns are grown just like sweet corn:

•  Sow directly into the garden when the weather has warmed up and there is no danger of frost. (soil temperature over 60 degrees Fahrenheit)
• Plant in blocks to ensure good pollination.  Plant seeds about 1 inch deep and 15 inches apart or every 7 inches apart in rows spaced every 30 inches.
• Corn requires lots of nitrogen, so apply compost prior to sowing.
• Allow corn to dry in the field for several frosts prior to harvesting.  Then husk and leave in a covered area to complete drying.
• Once dried, the corn can be ground using a hand turned grain mill ($70 and up) or grain attachment for your Kitchen Aid mixer ($130).