Here are a few harvest guidelines for summer crops:
Eggplants should be picked while they are still firm and glossy. Once their skins have become dull, they will be softer and have dark seeds, which can spoil the flavor. Eggplants don’t keep long, so use them soon after harvest.
Bell peppers and sweet frying peppers are sweetest when allowed to ripen fully to their mature color, yellow, orange, red, purple or mahogany. Bell peppers are often picked green, but their flavor will be a lot more pungent and they may be more challenging to digest.
Some of the hot peppers are traditionally enjoyed green – poblano, mulatto, jalapeno, Anaheim-type, while most of the rest are allowed to ripen to red (cherry, habanero, cayenne, lanterna, any chile dried for a ristra, etc.) orange (Bulgarian Carrot), or dark brown (Pasilla).
Many ‘black’ or ‘purple’ tomatoes have green ‘shoulders’ and should be picked when the fruit is plump and firm, and the bottom ½ to 2/3 of the fruit attains its rich mature color and the shoulders are still green. There are a few varieties I have found attain their most perfect flavor when plucked from the vine a day or two before eating, and allowed to ripen further on the kitchen counter (most notably ‘Purple Calabash’).
Green tomato varieties like ‘Green Doctors’, ‘Aunt Ruby’s German Green’ and ‘Green Zebra’ are ripe when you can detect a gentle blush of yellow infusing the green. Tomatoes should not be refrigerated, as it ruins their texture.
Tomatillos are ready to harvest when the fruit completely fills its papery husk and the berry is revealed.The color may still be green, or it may have begun to turn yellowish.
Summer Squash are quite varied (zucchini, crookneck, scallop, tromboncino, Lebanese, etc.), but most are best for sauté, steaming or salad when quite small. In Italy we found that zucchini was always sold when only 4” long and with the big orange blossom still attached. But of course there are good uses for the ones that got away, too.
Winter squash should generally be left on the vine or bush as long as possible for the flavors and sugars to develop, but should be harvested when its skin resists puncture by a fingernail and before the first hard frost. Many varieties of winter squash can be stored for months in the house and attain their best flavor after such ‘curing’ (kabocha-types, butternut, hubbard, and more).
Pumpkins can be harvested after their rinds are hard and skins have turned their ultimate orange, scarlet or white, depending on the variety. Be sure to leave 3 to 4” of stem attached so they will store well.
Melons are tricky, as there are so many types. Whenever possible, we have included tips in our descriptions of individual varieties on our website. Most canteloupes will ‘slip’ easily from the stem when ripe. For other types of melons, check the leaf closest to the fruit, and when it begins to yellow, the fruit is probably ripe. Some melon varieties give fruit color or texture clues. Watermelons are usually deemed ripe when the tendril closest to the fruit is dry and brown, or when the bottom side of the fruit is yellow.
Cucumbers vary enormously, too, so you may have to research the varieties you are growing. Generally speaking, cukes for pickling need to be small and very firm. We are growing Poona Kheera cucumber this year, and although we have read that it is still tasty when the skin has turned brown, we find it most delicious when still ivory-colored. Cauliflower should be harvested while the head of ‘curds’ is firm, the florets are tightly bunched and you cannot see any space between them, and the surface has not browned. Cucumber plants are most productive when kept picked. Oversized cukes can be fed to the chickens.
Celery Root (Celeriac) is usually best picked at about 3” diameter. It keeps in the vegetable drawer of the refrigerator for months. You can freeze puree of celeriac for future use in a potato soup or as a side dish.
Most Green Beans require daily inspection to catch them at their peak, when they are nearly full size, firm and crisp, and seeds are still small. Romano beans are more forgiving, and the long flat pods are still delicious and tender even when they are fairly large. To prevent the possible spread of diseases, don’t harvest beans when the vines are wet.
If you sowed Rutabaga in July, it should be harvested in October-November, when it will be tasty and tender. Small roots are the tastiest and sweetest. They keep for a long time at 33 degrees F. (in the refrigerator bin).
Kohlrabi from spring sowings should be harvested when small – less than 2”. Sowings made between July 10 and August 10 are less likely to become woody, and can remain in the ground well into fall, as they are hardy to about 10 degrees F. They can be allowed to reach 4-5” diameter.
Swiss Chard should be harvested continuously throughout the season. Once the plant is fully developed, harvest the outer leaves on a regular basis, always leaving at least 3 leaves around the core. Harvested this way, Swiss Chard is an incredibly productive crop, and many varieties continue to grow, with protection, through most winters.
Bulbing Onions are cured in the field before being harvested (unless you are going to use them immediately). When the tops begin to dry out and are falling over, withhold water, if possible, so the bulbs can mature in dry soil. After about half of the tops have fallen, push over the remainder, wait about a week and harvest the bulbs. Cure them for about a week to toughen the skins. This allows them to last much longer in storage. To cure them, spread the bulbs out on the ground in the sun, covering them at night with a tarp to prevent dew from wetting them. If the weather at this time is cloudy and wet, cure them on the floor of the garage, barn, shed or house. They are ready for storage when the necks are completely dry and shriveled.
Leeks are ready whenever they have reached ½” diameter or larger. Winter varieties like Bleu de Solaize are very cold-tolerant and can be left in the ground and packed in straw to prevent the ground freezing around them so you can pull them out as needed through the winter.
Parsnips taste best when left in the ground through a couple of frosts. Begin harvesting in October, and mulch heavily with straw or hay to keep the ground from freezing. You can continue harvesting as needed through the winter.