Zea mays var. Saccharata or Z. mays var. Rugosa
A few years ago, in the middle of summer, I threw some sweetcorn seeds into my flower bed, gave them some water, and kissed them goodbye.
Okay, not really (the kiss part). The seeds germinated and the seedlings grew a few centimeters – and then died. Naturally.
Because cool September came when they were young, and then October came in with its first snowfall.
I became wise after this waste of seeds and garden space. This year I refreshed my knowledge of maize cultivation and successfully grow large, fluttering green stems in my garden.
I still made some mistakes this year, but I also figured out how to fix them and I would like to share with you what I've learned.
Frankly, the idea of growing sweet corn can be daunting. How big will it be Does it create shade over your entire garden? How is it pollinated? When do you reap it?
If you have never grown sweet corn (Zea mays var. Saccharata or Z. mays var. Rugosa or sometimes Zea mays convar. Saccharata var. Rugosa) or if you need help with the corn that you grow in your garden I have covered you .
Are you ready to grow your own crispy, delicious sweet corn?
Before we grow, I'll share some surprising secrets about the history and nature of this common grain.
The sweet variety is mostly eaten as a suitable vegetable: corn is rich in fiber, folic acid, phosphorus, vitamin C, thiamine and magnesium.
Cultivation and history
Without humans, corn as we know it today would not exist.
While it is a wholegrain from the Poaceae grass family, Z. mays is nowhere to be found in the wild. Mesoamericans created corn from almost nothing nine thousand years ago.
And by "nothing" I mean that humble little grass, tea ink (Z. mexicana).
Photo by Mbhufford, Wikimedia Commons, via CC BY-SA.
With just a few edible grains in every tiny ear, Teosinte is not a food crop.
However, early Mesoamerican cultivators noticed a genetic mutation that removed the hard outer shell of Teosinte, which previously made the grain unpalatable.
They carefully stored and planted the special grains to make the corn we know today.
That was at least 5,000 to 7,000 years ago, as it turns out found the 5,000-year-old corn cob in the Guilá Naquitz Cave in Oaxaca, Mexico in the 1950s and early 2000s dated with carbon.
Indigenous peoples throughout America have grown corn for thousands of years.
The exact origin of sweet corn is unclear, but scientists generally know that the sweet variety may have been discovered accidentally when a recessive mutation of genes in corn occurred and changed the sugar and starch levels in the plant.
The people of the Iroquois nation grew this variety of corn into what they called "papoon".
During the American War of Independence, Lt. Richard Bagnal from the Army Brigade stole the variety from the Haudenosaunee.
Over the years, settlers and scientists have grown "Papoon" into what is commonly regarded as "original" sweet corn, or sugary-1 (SU).
We can thank John Laughnan, a botany professor and corn geneticist at the University of Illinois, for developing super-sweet corn in the 1950s.
Laughnan found the SH2 gene in sweet corn produced grains with up to four times more sugar and less starch than other maize varieties and developed super-sweet corn from there.
In the 1980s, another professor at the University of Illinois, Dusty Rhodes, discovered the tender, but less sweet, sugary corn (SE).
There are four main types of sweet corn that are grown and consumed today: SU, SE, SH2 and SYN.
Here's a quick breakdown of the differences between the four:
Standard sugary corn or SU is known for its sweet, creamy texture and should be consumed within a week of harvesting for the best taste.
The SU type contains more sugar and less starch than field corn, which is mainly used for grain and harvested when the kernels are dry.
The high sugar content in SU and other sweet varieties is the result of a natural genetic mutation that controls the conversion of sugar into starch in the plant and makes it sweet in the milk stage before the kernel is fully ripened.
Sugary Enhanced (SE)
SE is an improved version of SU, with a higher sugar content than standard sweet corn less sugar than super sweet (SH2).
An SE-type gene causes an increased amount of sugar in the kernels, which also leads to more delicate kernels.
SE is popular because after harvest, it retains its taste and texture much longer than standard SU types.
Super cute (SH2)
SH2 is – that's right, you guessed it – super cute.
In fact, it has four to ten times the sugar content of SU-type varieties. SH2 has a very low starch content when the seeds are fully ripened.
This fascinating type of sweet corn, abbreviated SYN, is a mixture of 25 percent SH2 and 75 percent SE, which results in crispy but tender grains that keep their taste well.
There are two ways to propagate sweet corn: from seeds or from transplants that you can find in some local nurseries.
Before you plant corn, it is important to know the right time and place for planting. Seedlings actually transplant pretty well, so you can start and grow seeds indoors or outdoors USDA hardiness zones 3-11
First, the weather is an important consideration. Z. mays is not cold tolerant. So wait two to three weeks after the last frost date in your region to plant your seeds.
Make sure your average early spring temperatures are not continuously below 60 ° F as it is difficult to successfully establish seeds in cold soils. The soil temperature should not be below 50 ° F for optimal germination.
To improve the germination rate of your seeds and accelerate germination, soak them in lukewarm water overnight.
Choose a planting site that receives at least six to eight hours of sunlight a day. The soil should be rich, so change your soil with well-rotted manure or compost before planting.
Sowing is easy. To sow seeds, dig a hole about an inch deep and put two to three seeds in it. Cover lightly with dirt and water.
You want to place holes about 7 to 12 inches apart. Arrange your seeds in a block pattern – essentially a four foot by eight foot square or similar – rather than in rows.
Each individual piston should be 7-12 inches away from the others within the square.
This is because Z. mays is wind-pollinated. If you plant your crop in a block, pollen is more likely to fall from the tassels onto the surrounding silk and not onto bare earth (or your carrots, peas, or whatever you've planted next door).
Next year I plan to plant four rows of sweet corn instead of two to help wind pollinate. Photo by Laura Melchor.
This grain harvest is a heavy automatic feeder and every plant needs some freedom of movement. When planting a row block, place each block about one to two feet apart.
Small gardens can successfully grow 15 to 20 plants in a 4 by 6 foot bed at a reasonable distance.
Keep the soil moist until germination, but not soaked. This can take anywhere from 10 days to three weeks
Once each plant has two sets of leaves, pinch the smaller or two seedlings every 7-12 inches so the strongest can thrive.
To start seeds indoors, do this about two weeks before your average last frost date.
Fill a seed coat with potting soil and drill a 1 inch deep hole in each cell. Drop two to three seeds, lightly cover them with soil and keep them evenly moist.
I learned early on that a plant becomes long-legged when a growing light is too far away. So keep it close to your growing sweet corn – as close as this light is to my young broccoli plants. Photo by Laura Melchor.
After germination, place the tray on a sunny windowsill that receives at least six to eight hours of light a day or more.
If you don't have a lot of sun, position yourself grow a light a centimeter away from the seedlings and adjust them as the plants grow.
Once each plant has two sets of real leaves, pinch all but one seedling per cell.
From a transplant
Sometimes you can find seedlings in a local kindergarten. Or you have successfully sown seeds indoors and want to transplant them outdoors in the garden.
Photo by Laura Melchor.
Make sure that the area you are grafting receives at least six to eight hours of full sunlight a day. The soil should be rich in organic matter, i.e. rework with well rotted manure or compost.
Dig holes about 7 to 12 inches apart. I wanted to fit more plants in my garden, so mine are more like seven to eight inches apart.
The holes should be the same size as the root ball you want to transplant.
Place the root ball in the hole and refill it with soil, being careful not to cover the stem. Water thoroughly, add a layer of mulch to keep moisture and weeds out, and watch your sweetcorn thrive!
How I grow
Sweet corn prefers organically rich, loose, well-drained soils with a pH of 5.5-7.0.
If you want to plant several varieties of sweet corn, maximize the space in your garden.
Unless it is the same variety or you have moved your plantings, each parcel should be at least 100 meters apart to avoid unwanted cross-pollination.
Corn is wind-pollinated: the tassels are the male flowers of the plant, and the silk and ears are female. Wind blows pollen from the tassels onto the silk.
Each strand of silk is connected to a single flower on the ear. Pollen from the tassel migrates down the strand and pollinates every flower, making the reproductive cells a delicious core.
If you plant several varieties together, different genetic traits of each variety mix.
This sometimes leads to unfavorable results: SH2 kernels, for example, should not be grown near other sweet varieties, since cross-pollination would suppress the gene, which makes it super-sweet and essentially turns it into field corn.
It is even worse to plant sweet corn near popcorn. I learned this lesson the hard way by literally planting corn and popcorn side by side.
When I realized that the popcorn tassels would pollinate the sweet corn, which would lead to starchy, tough grains (yes, I had planted them at the same time. I know. I know!), I had to plant the popcorn in the garden.
Don't try this at home! If the two varieties later pollinate each other, you will get crispy, chewy sweet corn. Photo by Laura Melchor.
I noticed my mistake when the plants were young, which made transplanting easy.
I simply used a trowel, carefully dug out the popcorn and transplanted it into a large, deep, square container.
Since I took the corn out of the fenced garden, I sprayed it with Plantskydd Protect it from moose.
The stems are big, green and happy in their container, which is at the opposite end of my property from the raised bed garden.
Photo by Laura Melchor.
Of course, the much easier solution to avoid cross-pollination is to plant different varieties that are far apart, or to stick to one variety.
When fertilizing, make sure that your sweet corn receives nitrogen, phosphorus and potassium regularly with a balanced NPK fertilizer such as 10-10-10.
Use it every two to three weeks according to the directions in the pack.
You can also add blood meal and bone meal according to the directions in the pack for a combination of nitrogen and phosphorus.
When your plants start to turn light yellow instead of deep green, they tell you something: Feed me! The yellowing of the leaves is a sure sign that the plant needs more nitrogen.
And if you don't give them enough phosphorus, the edges of the leaves can turn purple.
This has happened to both varieties that I grow.
I Bone meal added to the ground, which is rich in phosphorus, by sprinkling it and working it a few centimeters deep.
New green leaves emerged within a week.
As far as moisture is concerned, you want to give something to every plant an inch of water every week. Drip irrigation works well. Or water at the base of every plant.
Photo by Laura Melchor.
The last thing to keep in mind is that you may need to “hill” the corn to support the tall stalks.
To do this, simply hill earth about two to three inches high around the base to keep the stem straight.
Bring rich garden soil from your local garden shop to give the plants a nice boost of nutrients, or just pick up soil that is already in your garden and is not currently in use.
Repeat this process as necessary, usually every two to three weeks.
- Place different varieties at least 100 meters apart to avoid cross-pollination
- Fertilize every two to three weeks with a balanced product such as 10-10-10 NPK
- Provide the plants with an inch of water a week
- Hill every two to three weeks to provide support
Varieties to choose from
In this section I will introduce my favorite varieties SU, SH2, SE and SYN. For more options, see our summary of 11 best strains you can plant in your garden.
Bodacious, a full-bodied SE
While the maturation lasts up to 90 days, it is worth waiting for "Bodacious". This SE strain grows 8-inch flasks with 18 rows of sweet, milky grains.
Their delicious taste lasts 10 days after harvest. So if you plant a new seed block every two weeks, you'll have enough corn for all of your late summer and early fall cookouts.
Get your Bodacious seeds in different pack sizes at Eden Brothers.
Early Sunglow Hybrid, a SU in cool weather
The Early Sunglow Hybrid suitable for Zones 3-11 is an excellent choice for gardeners in cold weather. It also ripens in just 62 days. It's quick for corn!
With a golden color and a dainty four-foot stature at the time of maturity, this SU strain produces six to seven inch ears for your enjoyment.
Eat within two days of harvesting for the sweetest taste.
Find seeds in different pack sizes available at True Leaf Market.
Honey Select Hybrid, a wonderful SYN
This delicious mix of tender and crispy delivers 8 to 9 inch flasks about 80 days after germination.
The stems reach heights of five to six feet. Despite being large, they are not huge compared to other strains.
When sowing indoors, "Honey Select Hybrid" grows well in zones 4 to 11.
Find seeds in different pack sizes available at True Leaf Market.
Illini Xtra Sweet Hybrid, a super sweet SH2
This hybrid provides sugar content and the corn cobs stay sweet for days, giving you plenty of time to enjoy them after harvesting.
"Illinois Xtra Sweet"
With its ripeness, Ursprungi Xtra Sweet Hybrid grows to six feet tall and delivers 8-inch ears in 85 days. This variety grows best in zones 4-11.
Find packets of 200 or 800 seeds at Burpee.
Dealing with pests and diseases
Sweetcorn is susceptible to various pests and diseases. However, by checking your crop every day, you can avoid many problems.
Here are some common pests and diseases to watch out for.
Three of the most disturbing insects for sweet corn are aphids, cutworms and the European corn borer.
Teal maize aphids (Rhopalosiphum maidis) and greenish-yellow green peach aphids (Myzus persicae) slow down plant growth when they suck juice from leaves, leaving behind a sticky substance called honeydew that can develop soot mold.
Since aphids also love weeds, it is important to weed your garden well.
Use a strong one to get rid of aphids Water jet from the hose to repel them and then spray neem oil on each plant to prevent re-infestation.
Learn more about this in this guide Manage aphids in your garden.
These gray-brown worms are essentially decapitated seedlings that cut off seedlings from their elixir of life: the root systems of your young plants.
Not only that, but also cutworms – most commonly the species Agrotis ipsilon, Peridroma saucia and Feltia ducens – often curl up proudly next to their fallen prey, like the rascal next to the sad, dead lettuce plant shown above.
To keep these pests away, make an aluminum foil chain for each plant and place it around the stem.
Check the collar every day to make sure there are no signs of cutworms and to ensure that the stem does not rot.
Remove the collar before watering and replace it after about an hour so the plant has time to breathe.
As soon as the seedlings grow into strong young plants with thick stems, remove the collar.
Monterey Bacillus thuringiensis (Bt) spray
Spray existing worms with Bacillus thuringiensis (Bt) spray like this by Arbico Organics.
You can learn more about it Bacillus thuringiensis in this manual.
European corn borer
These nasty whitish caterpillars (Ostrinia nubilalis) attack tassels and often tear them from their stems.
Photo by Keith Weller, Wikimedia Commons, via CC BY-SA.
They also hollow out corn stalks by eating through stalks and chewing through the piston shafts, causing them to fall off the stalk. And they also like to nibble on the development of kernels.
In short, they are bad news for your garden. They often leave a bunch of food, also known as poop, when boring into a stem. So keep an eye out for strange masses under the leaves. The food looks a bit like sawdust.
To combat thuricide, treat as directed in the pack.
Try this product by Arbico Organics.
All kinds of diseases can infect your sweet corn. Here are some top annoyances.
Anthracnose is caused by the fungus Colletotrichum graminicola and shows up as brown, brown or even necrotic lesions on the leaves. Untreated, stems can eventually rot and kill the entire plant.
This mushroom thrives in hot, humid weather. It is therefore important to maintain sufficient airflow between your stems.
Also, remember to water at the base of each plant (instead of hosing it from above).
Manage an existing anthracnose infection as early as possible so your plants can continue to grow and produce ears.
Bonid revitalize biofungicide
For treatment, spray plants with Bonide Revitalize Bacillus amyloliquefaciens Biofungicide, available from Arbico Organics.
The Puccinia sorghi mushroom is easily recognized by its rusty spots on the leaves.
While it can affect all types of corn, it particularly loves sweet corn and is sometimes referred to as "ordinary corn rust".
A copper fungicide spray like this by Arbico Organicscan treat the disease.
Gray leaf spot
The gray leaf spot caused by the fungus Cercospora zeae-maydis appears as brown lesions on the leaves about two weeks before the production of tassels by the corn.
If left untreated, the lesions will turn brown, grow larger, and merge, killing entire leaves.
Fruit and vegetable spray
This environmentally friendly spray by Arbico Organics can help control outbreaks.
Harvest and preserve
Harvest for delicious fresh corn in the milk stage. This happens 18 to 20 days after the tassel. The silk is dry brown and the ear feels plump and firm when you put your hand around it.
At this stage, your plants are heavy and susceptible to strong winds. Insert a simple wooden post between two plants and attach two stems to each post with two cords or stretch bands.
This will help them to stand up until harvest time.
To harvest, gently grab one ear with your hand and bend or turn down. Wrap the ears in damp paper towels to preserve their flavor when stored in the refrigerator, and wait for the bowl to use.
Eat SU corn as soon as possible to get the best taste. SE, SH2 and SHY types keep better in the warehouse, giving you more time to eat or preserve them fresh.
The seeds can also be blanched and then frozen and stored in the freezer for up to 12 months.
This is the short version.
For complete instructions on harvesting and conserving sweet corn, go to our guide to harvesting corn.
Recipes and cooking ideas
There is an endless selection of delicious dishes that you can prepare with your sweet corn.
I prefer to grill it, cut it with butter, add a little salt and cut it to eat it.
I don't like it stuck in my teeth, so I eat it like a little kid. And it is good.
Photo by Fanny Slater.
My second favorite way to eat it is in the form of these divine sweet corn donuts our sister site Foodal.
I also love this roasted sweet potato, corn and black bean salad with spicy miso dressing for a perfectly light and tangy summer dish. You can find the recipe for this dish also on Foodal.
Photo by Raquel Smith.
Regardless of which recipe you use or come up with, it sure will taste a hundred times better if you make it with your own sweetcorn.
Brief instructions on growth instructions
|Plant type:||Annual cereal grass||Maintenance:||Moderate|
|At home:||Mesoamerica / North America||tolerance||Mild heat|
|Hardiness (USDA zone):||3-11||Soil type:||Rich and easy|
|Exposure:||Full sun||Soil drainage:||Well permeable|
|Time to maturity:||60-90 days||Companion planting:||Beans, pumpkins and other types of winter squash, sunflowers|
|Distance:||7-12 inches||Avoid planting with:||Celery, tomatoes|
|Planting depth:||1 inch (seeds)||Family:||Poaceae|
|Water requirements:||Moderate||Sorts:||Convar. saccharata var. rugosa var. saccharata, mays var. rugosa|
|Pests & diseases:||Aphids, cutworms, European corn borer; Anthracnose, ordinary rust, gray leaf spot||Aphids, cutworms, European corn borer; Anthracnose, ordinary rust, gray leaf spot||Aphids, cutworms, European corn borer; Anthracnose, ordinary rust, gray leaf spot|
Everything kitschy and wonderful
It's really exciting to see your little seedling grow tall and strong. There is nothing better than seeing how these tassels and silks form and then watching how the ears develop when you know you are looking forward to a tasty treat.
What do you love most about growing sweet corn? Let us know in the comments below!
And for more information on Grow corn in your gardenNext, take a look at these instructions:
Don't forget to pin it!
About Laura Melchor
Laura Melchor grew up to help her mother in the garden in Montana, and as an adult she brought her gardening skills home in Alaska in cold weather. She is particularly proud of the flower beds that she and her three-year-old son built with stones that were dug up from their small homestead in Alaska. As a freelance writer, she contributes to several websites and blogs on the Internet. Laura also writes novels and has an MFA from the Vermont College of Fine Arts.