Sweet corn has gotten even sweeter. With the advent of new hybrid varieties over the last 10 years, ears of sweet corn not only taste sweeter when freshly picked, they also hold their sweetness longer in the refrigerator. Before you go out and plant rows of sweet corn for a summer feast, there are some corn genetics you should understand.

What looks like a simple crop really has some interesting genetics behind it. Traditionally, open-pollinated varieties, such as 'Golden Bantam' and 'Hickory King', were grown by farmers and gardeners. These varieties, if grown in separate areas, will produce kernels true to type so they can be saved and planted the following year to grow the same variety.

When hybrid varieties came into their own in the mid-20th century, sweet corn varieties became more standardized and sweeter. Varieties such as the white 'Silver Queen' and bicolored 'Ambrosia' added disease resistance and adaptability. These hybrids produced more and bigger ears of corn. In order to grow these hybrid varieties, you have to plant new seeds every year because the kernels are not true to type.

In the last 20 years super-sweet hybrid varieties have taken corn to new heights. Sugary enhanced (Se) varieties, such as the yellow 'Bodacious' and super-sweet (Sh2) varieties, such as 'How Sweet It Is', produce as much corn as older hybrid varieties but have the ability to hold their sweetness longer after picking. They're more finicky about soil temperature when germinating, and some say their taste is "too" sweet, lacking the old-fashioned flavor. However, being able to store your corn in the refrigerator for days and still have it taste sweet when cooked is a big advantage.

For a good selection of sweet corn varieties, go to the Willhite corn pages.

Whichever varieties you grow, there are some basic techniques that need to be followed for planting, fertilizing, pest control, and harvesting.

Plant corn seeds 8 to 10 inches apart in rows 2 to 3 feet apart. Plant in multiple short rows, called "blocks," rather than in a few long rows. This will insure better pollination. A few weeks after planting, hill soil up around the base of corn plants to prevent them from blowing over in the wind or "lodging." Hilling also helps keep the corn patch weeded. Repeat the hilling again in a few weeks.

Since corn is in the grass family, it thrives on nitrogen fertilizer. Amend the soil in spring with compost and then sidedress when the corn is knee-high and again when the tassel (the top pollen-earing structure) forms. Use a high-nitrogen fertilizer, such as cottonseed meal, sprinkled along the row.

Keep the corn patch well watered and consider mulching with hay or straw after your second hilling to conserve soil moisture.