When to Harvest Home Grown Vegetables
Home grown vegetables can taste much better than those usually available in markets, but to be at their best, they need to be harvested at the right time. Many vegetables, because the process of ripening continues even after they are picked, should either be used immediately or stored in the refrigerator to slow down this process. This is especially true of tomatoes, sweet corn, snap beans, summer squash, beets and cucumbers. The sugars of some vegetables like corn and peas change to starch very rapidly unless refrigerated immediately.
Vegetables should be picked at the proper time not only to assure the best quality, but also to arrive at their optimum vitamin and mineral content. Vegetables and fruit left in the garden or on the tree too long will often become fibrous, tough or rotten.
In the case of vegetables, harvesting at the proper stage will also tend to keep the plants producing, since plants which do not have an abundance of leaves or fruit to develop and carry through to maturity will be able to produce more of both.
In order to harvest vegetables at its peak of tenderness and sweetness, it is important for home gardeners to be able to tell when that time is for each crop. The following methods have been determined through much trial and error, and should serve to facilitate this sometimes mysterious process.
Asparagus should begin to be harvested the second year after planting in the garden. They can be taken for only 2-3 weeks during this first harvest period. The net year this can be extended to 4-6 weeks and subsequently 8-12 weeks. Harvest the spears when they are 6-8 inches tall, but before the tips begin to separate. Snapping the spear off at the soil level will avoid the danger of cutting young roots and damaging crowns. Asparagus loses its quality quickly and should be eaten within a few hours after harvest unless it is quickly refrigerated.
Start harvesting when the pods reach about three inches long, while they are still young and tender. The beans and seeds inside the pods should be beginning to bulge the sides a bit. A snap bean ready to harvest should break easily with a snap as the name implies. Harvesting should be done fairly frequently during warm weather to keep the plants yielding. When picking beans, be careful not to break the plant. Use two hands. Pull the pods with one hand while holding the fruiting stems with the other hand.
For dry beans, allow the pods to remain on the plants until they turn brown and crispy. The beans can be removed from the pods and should be allowed to dry completely before storing.
Beets can be harvested whey they are 1- 1 ½ inches in diameter, and at this stage both tops and roots can be cooked together. Beets should never be allowed to get larger than 3 inches, because beyond this size they become quite woody.
Broccoli should be harvest before the buds begin to separate or start to show color. The center heads should be cut while the buds are still tight. After the center head is cut, smaller side shoots develop which will extend the harvest season up to a month or more. Keeping the side shoots harvested will keep the plants producing until the weather becomes too warm and causes bolting.
Heads are usable as soon as they become fully firm. Heads will split if they become over mature. Cutting just under the head to leave some basal leaves may cause small lateral heads to develop as a bonus.
Carrots can be harvested when they reach finger size and continue on through to the end. Harvesting will allow those that remain to quickly become larger. Carrots may be left inthe ground and used all winter long.laa
In order to get pure white heads on cauliflower, the outer leaves need to be tied together as soon as the head has reached a diameter of 2-3 inches. Examine the heads every few days to determine when to tie and when to harvest. Harvest the heads when they are still compact and fairly smooth. The bud segments should not be allowed to separate.
Harvesting can begin anytime the plants develop 4 or 5 leaves. Full grown leaves are cut 1-2 inches from the ground. Be careful not to injure the growing pont in t he center of the plant or the plant will not continue to produce new leaves. Very old leaves become tough and stringy. Always leave a few leaves on the plant so the plant can manufacture food to keep producing.
Collards can be harvested either by cutting the entire plant, or the bottom leaves may be taken off the plant periodically leaving the central growing point to produce more leaves. Be careful not to damage the bud or else production will be slowed down or halted completely.
Sweet corn should be harvested when the kernels are plump and in the milk stage, which is at the stage when the silks are dry and brown. The cobs should feel well-filled out and tight at the tip. At this point the kernels are about as large as they'll get, but they are still soft, tender and filled with a milky juice. Try not to peel husks away from the corn to see if they're ready. A little experience will enable the home gardener to feel the corn for tightness and readiness. Corn should be cooked immediately because the sugar in the kernels rapidly turns to starch and consequently toughness. Get them to the refrigerator as soon as possible if they can't be cooked right away.
Cucumbers should be harvested when the fruits are young and green and the seed still soft. A yellowish color on the skin indicates the seeds are mature and the fruit are beyond the eating stage. Picking should be done every other day. Cucumbers to be used for sweet pickles should be 2-4 inches long; those to be used for dills are picked when 5-6 inches long. Slicers should be allowed to become 6-8 inches. Any fruits which become over mature should be removed from the vines and thrown away. Leaving them on inhibits flower and fruit production.
Kohlrabi should be harvested when the enlarged stems have become 1½ to 3 inches in diameter. If they are allowed to become larger, they get tough and stringy, indeed, even woody.
The time to harvest lettuce depends a great deal on the type of lettuce. Head lettuce is ready when the head becomes firm. Bibb and leaf lettuce are harvested when the plants get large enough to use. If you have a limited number of leaf lettuce plants, just pull the older, or outer leaves for use, leaving the plant to continue producing leaves. In this way, leaf lettuce can be harvested over a long period of time.
Green onions or scallions should be pulled whenever they get big enough to seems worthwhile. They should be eaten immediately or quickly refrigerated. Onions harvested for storage should not be pulled until they are mature. After half the tops have fallen over, push over the rest to quicken maturity. They can be dug in a few days and must then be cured before storage. They should first be allowed to dry until the tops and outer scales become dry. Drying can be accomplished in the garden on top of the soil or, if there is the possibility of rain, underneath a shelter in a dry, well-ventilated area. After the tops are fully dried, they can be cut off 1½ to 2 inches above the bulb. The onions can then be placed in mesh bags or crate for stage in a dry area with the temperatures 30°-50° F. Sprouting and rooting indicate the temperatures are too high and conditions too moist.
Parsnips will be higher quality if allowed to remain in the ground until late fall or early winter. This increases the sugar content and enhances the flavor considerably. In storage, they should not be allowed to dry out, so it is will to store them in a moist medium, like sand, in a cool environment.
The pods should be swelled to nearly round and picked every 3-5 days. Allowing mature pods to remain on the vines will reduce production. Peas mature over a 7-10 day period. Best quality is obtained if they are picked just before they will be eaten. Sugar conversion to starch begin rapidly after picking. Edible podded peas or sugar peas are picked 2-3 inches long. If they remain of the plants longer, the seeds harden and the pods will toughen.
Peppers may be picked whenever they reach a size large enough to use, usually while they are still in the green or yellow stage. They may be allowed to turn red on the plant, at which point they become somewhat sweeter.
Harvest late varieties of potatoes when the tops have dried down but before any heavy freezes. Dig carefully to avoid injury and do not expose them to light for too long a period. They should be stored in a dark, well ventilated area where the temperature is around 45° F. Do not allow potatoes to freeze in storage. Early potatoes may be dug anytime they have reached a usable size. These must be used soon after harvest to avoid shriveling and deterioration.
Pumpkins and Winter Squash
Harvest these vegetables after the vines begin to dry, but before any heavy frost. The skin should be tough and have reached the correct color for the variety. With a sharp knife, cut the stems leaving a two inch stub on the fruit. Store in a warm, dry area. Don't wash them before storage.
Radishes should begin to be harvested at about the size of a dime. Allowing them to become too large may cause them to become woody or hollow and pithy. Often the tops of the roots will push above the soil when they are ready for harvest. Winter radishes which grow and mature in the fall can be pulled whenever they reach usable size.
Rhubarb may be picked for the first time the year after planting. Pick for only two weeks. In subsequent years, the harvest can go on about six weeks. Snap off the stems at the base after they have reached at least 12 inches in length. Pick only the older leaves and no more than two-thirds of the stalks of any one plant at a time. Allow the young stalks to continue to grow. After the stalks are harvested, trim off the leaves and discard them, since they contain oxalic acid, which is toxic.
Spinach is usually harvested from the time the plant have 5-6 leaves until jut before seed stalks develop. Simply cut the entire plant off just above the soil level with a sharp knife.
Summer Squash (Zucchini, Crookneck, Scallop, etc.)
These should be picked when young and tender. Yellow types should still be pale yellow when picked. Scallop squash should be greenish. The skin should still be soft when punctured by a fingernail. If the rind is too hard to be marked by the fingernail test, the fruit is too old to be used. Size should be 3-6 inches in length. Harvests should be carried out 2-3 per week. Pick and discard any fruit which has begun to mature.
For best quality and flavor, tomatoes should be allowed to ripen on the plants. Green tomatoes can be picked and stored in a cool, moist, dark place. To ripen them, simply bring into a warm room. Light is not essential for ripening. In the fall, entire plants along with their green fruits can be lifted and stored in a cool, frost-free area such as a garage or basement. Fruit can be ripened by exposing them to warmer temperatures. Refrigerating ripe tomatoes reduces the flavor and changes the fruit texture.
Turnips and Rutabagas
Both of these root crops can be harvested when they reach two inches in diameter. Turnips should not be allowed to get much large, because they become hollow and pithy inside. Rutabagas, on the other hand, do not demonstrate this tendency and consequently maybe left in the ground for use during winter.
By George Pinyuh (1981), Retired WSU Area Extension Agent, Reviewed by Jim Kropf, WSU Area Extension Agent, King/Pierce Counties May, 1998.