Harvest all firm, undamaged tomatoes with reddish skin, which will continue to ripen indoors, as will those with glossy, fresh green skin. Rock-hard green tomatoes make marvelous jam and are also lovely in chutney and salsa. To determine whether they will ripen, slice one open. If the seeds are surrounded with soft, clear gel and slide off the knife, you’ll eventually get ripe tomatoes. If you cut through dense, cloudy flesh and the seeds cut apart easily, you are better off making jam or chutney.
Before storing, gently wash your tomatoes and dry thoroughly. Remove all stems, which can poke holes that cause neighboring fruit to rot. If any fruit gets damaged in the process, use it immediately. Line berry boxes or box lids with newspaper and add a single layer of tomatoes. Crinkle more paper into “snakes” and place them between the rows, making sure no tomatoes touch each other. Nest smaller ones in open egg cartons, allowing each its own pocket.
Store tomatoes out of direct sunlight in a dry place with good air circulation. The kitchen, pantry or even garage is fine as long as the temperatures remain between the mid 60’s and mid 70’s. (Any higher and fruit may dehydrate, any cooler and the flavor will be ruined). Add a ripe apple or banana to provide extra ethylene, a natural gas that promotes faster ripening. The reddest tomatoes will ripen in 2-3 weeks while the greenest may need a month.
Tip: Never store red or green tomatoes in the refrigerator, because cold converts their stored sugars to starch, destroying that tangy sweet-tart tomato flavor in short order.