A “Potimarron” winter squash (Cucurbita maxima) ripening in my garden. This French heirloom produces 3-4 pound fruits that have a chestnut-like flavor. (Photo credit: April O’Meara)
This article originally appeared in the Arizona Daily Sun on September 26th.
Last Sunday was the autumn equinox and the official first day of fall. The equinox is a special time, as day and night, warmth and cold come into balance before the light gives way to the darkening days that take hold for the remainder of the year. In the garden, the autumn equinox signals the start of the squash, potato and corn harvest. But how do you know when your crops are ready to harvest? Here are tips for each crop.
Squash
Squash harvest timing depends on which varieties you grew and how you want to eat them. For starters, summer and winter squash need to be harvested before the first hard frost as the cold will kill the plants and damage their fruit.
Although all squash can be eaten when small, squash that produces tender skin and few seeds are usually picked young throughout the season, hence the name summer squash. These are usually “zucchini,” “scallop” and other similar varieties. Winter squash, on the other hand, refer to varieties such as “pumpkins” that have outstanding long-term storage qualities. Winter squash are ready when the rind is tough enough to not be punctured by your fingernail. If your fingernail can indent the flesh, the fruits won’t store well and are better eaten right away. To further aid the storage process, be sure to leave about one inch of stem attached when you cut your squash from the vine.
Potatoes
Although you can harvest “new” potatoes a few weeks after the plants have flowered in late summer, spuds grown for winter storage should be harvested 2 to 3 weeks after the foliage has browned and died back to the ground in September, October or early November.
To check if your crop is ready, take up a few potatoes to make sure their skins are thick and tough and not easily rubbed off. If the skins are firmly attached, then use a spade or pitchfork to gently lift and loosen the soil around your plants, trying not to damage the potatoes. Once loosened, I like to grub through the soil looking for the potatoes with the same excitement as an Easter egg hunt in spring. There is something immensely satisfying about running your hands though damp cold soil teaming with earthworms and the smell of fresh potatoes on a crisp autumn day!
Corn
Harvesting corn depends on the variety of corn you choose to grow. Flour, flint and dent varieties are harvested once the ears have completely dried on the stalk. These corns are used for cornmeal and popcorn. For sweet corn, the first ears or corn cobs to ripen are usually those in the center of your planting. To test for ripeness, select an ear with silks (the thread-like strands found between the corn husk and ear) that have turned brown but are not entirely dry. Now, feel the ear by pinching through the husk. The end of the ear should be blunt rather than tapered. Peel back the husk and examine the kernels. They should be light in color and squirt a milky sweet juice when pressed with your fingernail. This is called the “milk stage” and is the best time to harvest sweet corn. Be sure to roast and devour right away as corn in this stage does not keep for very long.
If you open the husk and see few-to-no full kernels, then you may have had a pollination issue. Corn is a wind-pollinated plant with imperfect flowers – having male and female parts on separate flowers. The tassel, at the top of the plant, is the male flower. Pollen is shed from the anthers, along the tassel branches. The ear has the female flowers and is located on the stalk. This is where the silks emerge. Each strand of silk is actually a long stigma, which is receptive to pollen along its entire length. Each silk is in turn connected to a single immature kernel. And so, if during the flowering process there wasn’t enough pollen grains that landed on each silk to fertilize it then those kernels will not grow to maturity.
Nate O’Meara is the Executive Director of The Arboretum at Flagstaff.
