My dad never grew corn in the garden he tended outside Denver, where I grew up. He was from Nebraska and Mom was from Iowa, so they certainly knew what corn is supposed to taste like. I know Dad tried growing it a couple of times, but the conditions in Colorado made it hard to produce a crop that tasted even vaguely like what folks from America’s Corn Belt expected. And apart from growing an obscure Native American hominy corn from the Northeast for a couple of years to help maintain seed banks for Native Seeds/Search, I’ve never done much with corn either. In the past week, however, I’ve had a couple of conversations with folks who were bummed about having been fed the esoteric plate of corn served up in the last two installments of The Practical Gardener without getting the how-to side of the subject as well.
To augment my own limited experience, I decided to call my gardening pal Yanna Fishman, who has a legendary half-acre garden east of Old Fort. Each year, about 15 percent of her garden is devoted to sweet corn, field corn and popcorn. What follows is a mix of her good counsel and what I’ve learned.
Because it’s a grass, corn requires abundant nitrogen. It’s also sensitive to deficiencies in trace nutrients such as magnesium, boron, zinc and iron. Scientists, in fact, use corn to study trace-mineral deficiencies in plants (which commonly show up as recognizable spots or discolorations in the leaves). The old-timer who lives down the road from me uses rotted barnyard manure to grow his sizable patch of corn each year. Studies have shown that manure has the trace elements corn needs (and, of course, the nitrogen that this heavy-feeding crop also requires). If you don’t have access to manure, a biennial amendment of a mined marine product called greensand (spread at a rate of one coffee can per 100 square feet) will give your plants the slow-release value of the trace minerals it contains. There are also a number of slow-release organic fertilizers that will give your crops what they need; the one I use has a 4-5-4 NPK rating; I keep it stored in a plastic trash barrel with a waterproof lid.
Corn requires a lot of water during the growing season (12-24 inches per year, depending on the variety). One thing I do know from experience is that corn leaves roll up lengthwise when they lack water, but you should never allow your plants to even get to the point of raising that international distress signal. One way to make sure your crop can utilize most of the water you send its way is to mulch with straw, rotted hay or composted leaves between the rows. Studies indicate that allowing corn to endure this stress when it is shedding its pollen can significantly alter its ability to produce ears, because the pollen may not be viable. On the other hand, overhead watering during that time will wash the pollen to the ground, which also renders it useless. Conservation and productive pollen-release are two good arguments for using soaker hoses to water corn.
Mulching corn is beneficial in another way as well. Corn will eventually develop a magnificent root system, spreading 3 or 4 feet laterally and equally deep. During the first four to six weeks of life, however, a corn plant’s very life depends on secondary roots that travel sideways just below the surface of the soil. Those deep-seeking roots don’t really start submerging until the pollen begins to shed. And in the meantime, the shallow roots are susceptible to damage accidentally inflicted while hoeing weeds between the rows. Cutting those roots may not kill a young corn plant, but it could severely hamper the plant’s growth pattern. Mulching eliminates the need for hoeing, keeps weeds at bay, and cuts water loss due to evaporation.
If you look at most corn fields grown by home gardeners, you’ll notice two or three different sections, all at different stages of development. That’s because the gardener has staggered the plantings to spread out the harvest. The beauty of staggered plantings is that you can grow different varieties close by without fear of them cross-pollinating, as long as the plants aren’t all dropping pollen at the same time. The classic staggered-planting interval is two to three weeks, but Yanna says this is somewhat deceiving because, as the hotter summer weather comes on, corn gains ground quickly — so a variety that’s planted in late spring, two weeks after the initial crop, will be ready for harvest at almost the same time. To compensate for this, Yanna plants her fastest-maturing variety first and a slower-maturing variety a couple of weeks later. She has already planted a quick-maturing variety of sweet corn in her garden this year, and she’ll soon be sowing some big heirloom variety such as “Hickory King,” which she’ll dry after harvest to use for making corn bread.
For years, Yanna used the back of her station wagon as a drying chamber for her field corn. She would cover the windows with a blanket and crack the window a bit to let out moisture. This low-budget drying technique is worth noting; it’s especially handy when your corn is approaching maturity and is threatened by late-summer storms.
Yanna has always planted her corn in trenches, gradually filling them with garden soil as the individual plants grow — even hilling up the soil around the stalks as they reach ground level, to ensure strong root structures that can stand up to winds. And when the stalks are about 6 inches above the top of the “hills,” Yanna capitalizes on that enhanced structural integrity by planting a single bean plant at the base of each stalk.
If all this sounds like a lot of work, here’s an added reward, compliments of Yanna. Dry a few ears of sweet corn and remove the kernels. Parch the dried kernels in a heavy skillet with a minimal amount of olive oil in the bottom. The kernels will swell up, and voila! — you’ll have a hard, sweet, crunchy taste treat that kids and adults alike will go crazy over.