These tomatoes are nearly ripe. Pick fruits when they are firm and fully colored. When temperatures are above 90°F, pick tomatoes when they begin to develop color and ripen them indoors.

Whether you started your first garden this year or are a veteran grower, we’re coming up on the heart of harvest season. One of the advantages of homegrown vegetables is that you can harvest produce at its peak quality and flavor.

But knowing when to harvest a crop can be difficult, especially if it’s your first time growing it, says Ken Johnson, University of Illinois Extension Horticulture educator.

“Almost all vegetables are best when harvested early in the morning,” Johnson says. “If you can’t harvest in the morning, keep produce out of direct sunlight and cool as soon as possible.”

When it comes time to harvest your vegetables, make sure plants are dry. If you harvest while plants are wet, you risk spreading diseases. It’s also important to handle plants with care and avoid damaging them.

“Damaged areas can provide openings for diseases to enter,” Johnson says. “If the vegetables you are trying to harvest don’t easily come off, cut them off with a knife or pruners to avoid damaging the plant.”

Snap or green beans should be picked when the pods are fully grown but before the seeds have started to get large. The beans should be crisp and snap easily. When picking, break off the stem above the cap and harvest frequently.

Cucumbers should be harvested before their skin turns yellow and the seeds become hard. The size of the cucumber will vary depending on the type. Pickling cucumbers are usually picked when they are between 2 and 6 inches long. Slicing pickles should be picked at 6 to 8 inches long and burpless should be 1 to 1½ inches in diameter and up to 10 inches long.

“Cucumbers develop quickly, so plants may need to be checked every other day,” Johnson says.

Peppers can be harvested at any size. Green bell peppers are typically picked when they are mature and about 3 to 4 inches long, firm, and green. If you are growing colored bell peppers, wait until the fruits change color.

“One way to tell if the fruit is mature is that they will easily break off of plants when picked,” say Johnson.

Hot peppers can also be picked at any stage but are typically picked when fully ripe. The mature color of the fruit will be different depending on the variety.

Summer squash — straightneck, crookneck, or zucchini — should be harvested when they are small and tender. Pick when the fruits are 2 inches or less in diameter and 6 to 8 inches long. “When growing conditions are favorable, you may need to harvest every other day or daily,” Johnson says.

Winter squash —  acorn, butternut, pumpkins —  can be harvested when the fruits have turned a deep, solid color, no longer have a glossy appearance, and the rind is hard. Leave at least 2 inches of stem attached and harvest all squash before heavy frosts arrive.

Tomatoes are at their best quality when allowed to ripen on the vine. Tomatoes should be firm and fully colored. During hot conditions, 90°F, tomatoes will quickly soften, and color development is reduced. During these conditions, pick tomatoes when they begin to develop color and ripen them indoors. If plants still have fruit on them in fall, you can harvest mature green fruit before the first frost and ripen them indoors.

For more information on vegetable gardening, connect with your local Illinois Extension county office at go.illinois.edu/ExtensionOffice.