By Dan Gill

LSU AgCenter Horticulturist

(10/07/16) Harvesting properly and at the right time is critical to getting the best quality vegetables from your garden. At this time of year, we have both warm-season vegetables planted back in August as well as cool-season vegetables that will grow through the winter. Many people have the following plants in their vegetable gardens this time of year.

Warm-season vegetables

Often, warm-season vegetables are still producing when frosts begin to threaten. Make sure you harvest all pepper, eggplant, tomato and other warm-season vegetables prior to a killing frost below 32 degrees.

Harvest peppers anytime because they can be eaten both immature (green or purple) or mature (red or orange). Harvested peppers – hot or sweet – should be refrigerated. Extra peppers that cannot be used within seven to 10 days can be seeded, chopped and frozen for later use.

Eggplants do not store or freeze well. Give away extras that cannot be eaten within several days of harvest. Harvest eggplant fruit while it is immature and the skin is still shiny and dark purple. You may also prepare cooked dishes with the eggplant and freeze them for later use.

Fall tomatoes ripen slowly on the plant once cooler temperatures begin. Harvest any fruits as they begin to blush pink. They will ripen and turn red more rapidly at room temperature indoors, and quality will not suffer. You do not need to put them in a window to ripen because light is not important to the ripening process; it is determined by temperature. Of course, unripened fruit may be used in your favorite green tomato recipes.

Snap beans should be harvested when pods are still tender and the seeds are very small. If beans are allowed to mature on the plants, they can be shelled and cooked as dry beans.

Cool-season vegetables

Bulbing onions and garlic are generally ready to harvest in May or early June. They should be dug when the leaves are half-dead and the tops are falling over. At this point the bulbs are as big as they will get. Harvest on a sunny day and allow the plants to remain in the sun for at least one day to dry. Remove the roots from the base and cut the stem about one inch above the bulb.

Bunching onions and green shallots are harvested for their flavorful foliage and small white undeveloped bulbs. You can harvest the foliage simply by cutting it as needed. To harvest the bulbs along with the foliage, dig the whole clump, separate one-half to two-thirds of the clump for harvest, and replant the remaining clump back into the garden to continue producing.

Root crops are harvested when the root is the proper diameter. Usually, the top of the root is readily visible at ground level. Feel free to brush aside soil at the base of the leaves if you need to for checking. Harvest radishes and carrots when the root is about 1 inch across, turnips at 2-3 inches and beets at 2 inches.

Broccoli should be harvested based on the size of the flower buds, not the size of the head. When the largest flower buds in the head are about the size of the head of a kitchen match, it’s time to harvest. If you leave the head too long, you will begin to see yellow flowers. Smaller florets will form after the main head is harvested, so leave the plants in place.

Harvest cauliflower while the head is still smooth and tight. Again, you cannot go by size. If the head begins to get rough and the florets begin to separate, harvest immediately. No more heads will form, so pull up the plant when you harvest the head.

Harvest cabbage when the heads feel hard and solid when squeezed. Unlike broccoli and cauliflower, cabbage does not have to be harvested immediately when it is ready but may be harvested over several weeks.

Collards are harvested by cropping – which means just removing the lower leaves. As the plants grow, break off the largest, lower leaves from each plant. This allows the plants to continue producing over a long period. You may also harvest the entire plant when the leaves reach full size, but that ends the harvest.

Leaf lettuces tend to be the easiest lettuces to grow and are often more productive. Harvest by cropping for an extended harvest season. Or you can harvest the whole plant when it reaches full size. Semi-heading lettuces (bib, buttercrunch, romaine) are harvested once the plant reaches full size by cutting the stem at ground level. Heading lettuces are considered more difficult to grow successfully here. Harvest when a firm head has formed.

Vegetables that can be planted in October includes beet, broccoli, cabbage, carrot, cauliflower, celery, Chinese cabbage, collard, endive, garlic, kale, kohlrabi, leek, lettuce, mustard, onion, peas (English and snow), radish, rape, rutabaga, shallot, Swiss chard and turnip as well as many herbs, such as thyme, sage, rosemary, oregano, French tarragon, lavender, chives, cilantro, dill, mints and parsley.

Harvest fall tomatoes as they begin to blush pink. They will ripen and turn red more rapidly at room temperature indoors, and quality will not suffer. Photo by Rick Bogren

Harvest peppers anytime because they can be eaten both immature (green or purple) or mature (red or orange). Photo by Rick Bogren

Harvest cabbage when the heads feel hard and solid when squeezed. Photo by Mark Claesgens