University of Minnesota Extension Pine County Master Gardener
You’ve been gardening for weeks – preparing the soil, planting, thinning, watering and weeding. Now it’s time for the harvest to begin. So how does one know when to harvest? You want to pick it when quality and flavor are perfect. With some crops it’s easy, but with others it’s a real challenge.
The easy crops are those with a wide season for harvest. Onions are harvest-able any time from the green onion stage until the bulbs stop enlarging and die back. For good storage, you want to wait until the tops are completely dead and dry.
Root crops like radishes, carrots and beets start to push up out of the ground slightly when they bulb up and one can see the diameter of the bulb at the soil surface. One can start harvesting carrots from when they reach about one inch in diameter. You can also leave them in the ground for later harvest until a hard frost comes. Radishes are also ready when they reach about one inch in diameter. Left too long, they get tough, hot tasting and “bolt.” The exception is the German Giant type radish which can stay tender until it reaches ping pong ball size before it bolts. Beets are at their best when two to three inches in diameter.
Beans and cucumbers need to be harvested routinely, usually every other day so that they keep producing. Pods of beans left on the plant begin to bulge and get over-sized and tough. Mature beans, left unpicked, cause the plants to cease flowering until they are removed. Cucumbers can be picked whenever the fruits reach a size that you want them. Fruits that get larger than desired should be removed from the plant to stimulate the vine to continue flowering and producing more fruits.
The most challenging crops to harvest at just the right stage are melons. We’ve all likely experienced the disappointment of cutting open a melon that is either under or over ripe. Small subtle changes in appearance signal ripeness. Both cantaloupe and watermelon seem to ripen quickly and get over ripe in a few days. Checking for ripeness often is essential. When cantaloupe fruits ripen, their color changes from pale green to yellow-tan under the ridges of the shell. They develop a layer between the fruit and stem that will break away with very little pressure. They also produce a sweet smell when ripe. If you happen to pick cantaloupe that is slightly under ripe, it will continue to ripen. Watermelon, on the other hand, does not ripen further after harvest, making it the hardest vegetable to capture at the peak of ripeness. The belly of the watermelon is the surface where the fruit rested on the ground and it turns from white to creamy yellow when ripe. The challenge is how yellow it should get before getting over ripe. Melon experts can tell ripeness by thumping the melon with a finger. The sound reveals ripeness. It takes experience to recognize the sound of ripeness, more experience than I possess.
Some helpful websites to check out are: extension.iastate.edu for their Vegetable Harvest Guide and garden.org, a site provided by the National Gardening Association. To learn more about vegetable harvest, nutrition and succession planting, join the Pine County Master Gardeners at the Pine City Community Garden Monday, Aug. 19 for the next program in our Summer Gardening Series. The programs begin at 6 p.m. and are open to everyone at no charge.