© 1998 Henrik Nordström

The last couple of summers have not been ideal for growing corn around here, since spring and early summer were cold and wet. Last year, the fall rains started unusually early, so many gardeners never got their corn to ripen. It is, however, quite possible to get good and tasty corn crops in Seattle, even during marginal years.

Two factors are key to success with corn: Choosing a locally adapted variety and getting the seeds to germinate fast. The regular sweet corn varieties germinate at lower temperatures than the sugar-enhanced and super-sweet varieties, and after several instances of low germination ratio with the latter two, I almost exclusive grow the first kind. I think that regular sweet corn is just as tasty as the latter ones, provided that you eat it soon after picking, since it looses its sweetness faster. In 24 hours, it can loose half of its sugar content.

Regular sweet corn varieties will germinate well in soil temperatures in the 60s, while the sweeter types of corn require over 70 degrees in the soil. Early Sunglow is one of my favorites. It is also a fairly low-growing variety, so it does not shade the garden as much as the taller ones. I soak the seeds in a glass of water for a couple of days before sowing to soften the seed coats. Some gardeners prefer to soak them until they germinate, but this makes the handling of the soft germinated seeds more difficult when planting. It is very important to always sow your corn in blocks of a minimum of 4 x 4 plants about 10 inches apart in all directions, since corn is wind-pollinated and sowing in a block ensures more complete pollination of the ears, preventing "missing" kernels. Never sow just a single row of corn. Corn needs plenty of fertilizer mixed into the bed before sowing. I poke holes about 1.5 inches deep and 10 inches apart and drop three seeds into each hole. After covering the holes, I water the bed with warm water to maintain the soil temperature and cover the planting with a sheet of clear bubble wrap. The air in the bubbles store heat in the daytime and give it off to the soil during the night.

The corn seeds should germinate in a week or less. If they have not germinated in 10 days, the soil is too cold or the seed is not viable, and the bed should be resowed. As soon as the seeds germinate, the plastic must be removed to prevent the young seedlings from frying. If more than one seed germinated in each planting hole, I carefully cut off the extra plants when they are a couple of inches tall. Trying to transplant them is not worth it, because this will only damage the roots of the seedlings you want to keep.

I sow my corn in early May, even though the seed catalogs recommend late May, since even the earliest varieties require over 90 days here to ripen. When the corn blooms about 8 weeks after sowing, I shake the plants to make sure that the pollen falls evenly over the silks and pollinate the ears.

The corn stalks will often develop side shoots. According to research, these side shoots should be left in place, since they participate in generating sugar for the developing ears. In a good summer, some of the side shoots may also develop ears, so one plant may produce up to 4 ears. Normally, however, the gardener can be quite happy with two fully developed ears per plant.