Home growers like you can become savvy harvesters by remembering just a few tips about each crop.

Tomatoes. Tomatoes should be picked when they are firm and have reached full color -- crimson, red, yellow or other colors depending on the variety. It's probably a good idea to pick a range of ripening tomatoes every few days and let a few finish ripening after picking so you'll always have fresh, ripe tomatoes for salads and recipes. The ripening tomatoes will have slightly lower amounts of vitamins and minerals than the fully ripe fruits.

Peppers. Green peppers are picked and used before full ripeness. Gauge ripeness by the size estimate on a seed packet or in a seed catalog. Firmness also is a ripeness indicator. If the pepper feels as though it has thin walls, it is not ripe. When green peppers are allowed to ripen, they can turn into a rainbow of colors depending on the variety. If peppers have ripened to full color, use them quickly because they have only a few days of shelf life at that stage.

Zucchini. Zucchini tastes best when harvested at lengths from 6 to 10 inches. Don't let them grow longer than a foot. After 8 to 10 inches, zucchini gets tough and develops more seeds. Longer zucchini that escaped your attention during picking can be grated, or breaded and fried.

Cucumbers. Pickle cucumbers should not be grown beyond approximately 4 inches. Other types, such as some burpless or Oriental varieties, can reach ripeness at nearly 15 inches. The longer cucumber types are ripe when they retain a hint of the ridges and spinyness associated with immature cucumbers. Think of a cucumber as a balloon, if it's inflated to a perfect smoothness, it's too far gone.

Eggplant. Estimate ripeness by comparing the crop to the size and shape described on the seed package or catalog. The eggplant also should be shiny and glossy. The stem and cap should be mint green or purple, depending on the type.

Melons  (muskmelons and cantaloupes). Most melons are perfectly ripe when they separate from the vine easily. A small tug should be enough. Other melon types are ripe when they turn from a greenish hue to a more yellow or orange color.

Watermelons. Each watermelon will have a pigtailed tendril of growth near the stem. As that tendril browns or dies, look at the underside of the melon. The underside should be slightly yellow. Inside, the seeds will be deep brown to black, not light tan.

Carrots. Because carrots invest most of their early growth into the plant leaves, the carrot, or root, does not mature until late summer or fall. Danvers varieties should be harvested when they reach about a 2-inch diameter. Nantes varieties should be picked when they reach 1 inch in diameter. To check diameter, just run your finger around the base of the plant and uncover the top of the carrot.

Leaf Lettuce and Spinach. Although gardeners can harvest the entire plant head early to thin the crop, I recommend removing and using the outer leaves of the plant as you need them. The plant will keep producing leaves until a killing frost. You can harvest chard and rhubarb the same way.  

Onions. Because most onions are grown from sets, which means many of the plants grow too close together, it is recommended you thin out the plants. Onions are ready for final storage harvest when about half the plant leaves have turned brown or drooped. Push the rest of the leaves over and pick the onions about a week later. Leave the onions in the field to dry for a few days, then hang them. Onions forming a seed head -- the green shoot that looks like a spear coming out of the onion -- should be eaten immediately, because they won't dry out adequately for storage.

Snap (green or wax) Beans. The key to harvesting snap beans is to pick them before the pod shows any seed development. There should be no swelling where you can see the seed in the bean. Also, the bean should literally snap when you break it. If they're over rippened, the bean will be rubbery.

Broccoli. Broccoli plants produce a large central head comprised of tightly bound buds. The head should be harvested before any hint of yellowing appears and before the buds separate. Some broccoli varieties will continue to produce large shoots even after the central head has been harvested.

Flat Edible Pod Peas. These crops, known as Chinese peas or snow peas, should be picked when still flat, before the pod reveals the outline of the internal seeds. It is recommended that you check the size description on the seed packet or catalog as well.

Round Edible Pod Peas. Also known as snap peas, these varieties are the sweetest and most tender peas. They should be picked when fully round and smooth. The color should be mint green.

English Peas. The pod should be shiny and swelled enough to suggest the outline of the peas. All pea varieties should be cooled immediately after picking, because their sugars will turn to starch under warm conditions.