Texture, Color Show Best Time to Harvest

Question: Do you have any guidelines for when to harvest my summer vegetables?

J.B., Stanton

Answer: Generally, harvest summer vegetables when they’re young and tender. Check them daily and if possible pick them in the early morning when they are crisp and cool.

Below are some guidelines for harvesting the most common summer crops:

Green beans: Pick them while they are young (start at around 4 inches), once the immature seeds fill the pod but before beans inside have started to swell and become bumpy. The outside should still be somewhat velvety and the beans that fill the pod area should be light green (creamy white for butterbean types).

If a pod easily snaps in half when bent, it is ready to harvest. Beans tend to lose flavor and become somewhat tough if they are allowed to grow too large. By harvesting pods frequently, you can also prolong production.

Cantaloupe: A cantaloupe is fully ripe when a slight crack completely circles the stem where it attaches to the fruit, and the fruit falls into your hand without pulling. The skin should be mottled, rough and dry, and a fresh melon aroma will be apparent.

With melons such as honeydew and casaba, don’t wait for the outer shell to get dry. You should pick them when the color changes from bright green to a more subdued lime or almost tan for honeydew and a deeper, lemony color for casaba. The stem will also lose its fresh, rounded appearance.

Corn: The objective here is to harvest when there is a maximum sugar content and not too much starch. Once the silks turn brown, but before it dries up, and the husks are tight and full to the top, nick a kernel with your thumbnail.

If the liquid is milky and not clear, it is ready to be picked. If you notice slight shriveling of the kernels, you have waited too long, the corn will be too starchy and the sugar content will have dropped. Corn is usually ready to harvest about three weeks after the silks appear.

Cucumbers: Harvest cucumbers early and often. If left to mature on the vine, production will slow or even stop. Harvest slicing types when they are 8 to 10 inches long; pickling types at about 3 inches.

Mature cucumbers with small seeds, dark green skin and crisp texture taste the best. Yellowing of the skin often indicates that the cucumber has tougher seeds and is somewhat sour.

Eggplant: Begin harvesting when the fruit is about 4 to 6 inches in diameter and continue to pick them for increased production. The color of the eggplant should be uniform; the skin should still be glossy and the flesh should not spring back when you press it with your thumb. If the flesh does spring back, it is still green.

Dullness, brown skin or seeds indicate the eggplant is overripe. Use pruning shears or a knife to remove the fruit from the plant.

Peppers: Harvest them when the fruit is well formed, with crisp, thick stems. There should not be any soft spots or wilting of tissue. You can leave a few fruits on the plant to turn red (the flesh will be sweeter); but not all, because the plants will stop blooming unless you pick some.

If you are growing hot peppers, leave them on as long as possible for maximum heat. Allow hot peppers that you plan to dry to ripen on the plant. Hot peppers turn red when ripe.

Summer squash: Summer squash should be harvested when the fruits are immature (for example, zucchini should be picked when it’s 3 to 4 inches long; yellow crookneck squash, 2 to 4 inches long, and patty pan, the size of a half-dollar).

Pick squash when the skin can be easily pierced with your thumbnail.

If allowed to grow too large, they lose flavor and become tough. Tiny ones can be picked with the blossom still on and cooked blossom and all. As with the other summer vegetables, harvest frequently to maintain production.

Tomatoes: There is an art to recognizing peak flavor, texture and color in tomatoes. The first thing to assess is whether you planted a determinate or indeterminate variety. Determinate varieties ripen more or less all at once (over a period of three weeks).

Indeterminates offer one or two tomatoes at a time and produce over a two- to three-month period.

A ripe tomato is soft on its shoulders (the swelling around the base of the stem), fully formed and plump with even, deep color. If possible, leave tomatoes on the vine until they are red and ripe, for the fullest flavor.

Splitting skin is a sign of overripeness.

You can always rely on color. Many heirloom tomatoes ripen unevenly. Pick them when they are smooth-fleshed and full (even if their shoulders are a bit green).

Watermelon: Watermelon are ready to be harvested when the discolored spots on the bottom of the melon turn from pure white to a creamy yellow color, and the tendril on the stem closest to the fruit darkens and dries up.

Thumping for sound is a technique often used, but can be a bit unreliable. Rap the side of the fruit with your knuckles. A light or metallic sound indicates the fruit is still green; a dull sound means it is ripe. If you use this method, do it in the early morning, because during the heat of the day or after the melons have been picked for some time, they all sound ripe. Use a sharp knife to remove melons from the vine.

Baby vegetables: These are a special category. According to Renee Shepherd of Shepherd’s Seeds in Felton, Calif., “Most baby vegetables are bred to either gain high flavor early in their development [so they can be harvested before they grow to a normal size] or they are bred to stop their growth early on, but retain all the flavor of a mature plant.”

Baby vegetables are picked roughly at the same time of year as the larger vegetables.

Have a problem in your yard? University of California Cooperative Extension (UCCE) Master Gardeners are here to help. These trained and certified horticultural volunteers are dedicated to extending research-based, scientifically accurate information to the public about home horticulture and pest management. They are involved with a variety of outreach programs, including the UCCE Master Garden hotline, which provides answers to specific questions. You can reach the hotline at (714) 708-1646 or send e-mail to ucmastergardeners@yahoo.com. Calls and e-mail are picked up daily and are generally returned within two to three days.