Here's what to do if you still have tomatoes on the vine.
It's officially fall today, and that means tomatoes are on borrowed time -- even if we're lucky enough to have mild weather well into October.
"Tomatoes like it hot," said Jeff Gillman, associate professor of horticulture at the University of Minnesota. "It's not going to be really hot again. I wouldn't expect much more out of tomato plants."
If you have tomatoes on your plants that are close to ripening, you might as well leave them on those plants, Gillman said.
"They'll probably ripen faster inside where it's warmer, but the flavor is better when they're vine-ripened," he said.
However, with temperatures expected to fall into the 30s this weekend, you might want to cover your plants.
"Put an old sheet or blanket over them," suggested garden writer Deb Brown. Tomatoes in pots can be brought indoors for the night.
If you're concerned about freezing, it's fine to pick tomatoes that are close to ripening and bring them inside. Look for tomatoes that have just started to blush red or have turned from apple green to a lighter creamy green, Brown advised. Place tomatoes -- separately, rather than piled together -- on a countertop or other surface, but not on a windowsill, she cautioned. Tomatoes ripen more evenly when they're not in direct sunlight.
Barring a freeze, tomatoes left on the vine should be OK.
"I wouldn't pick mine," Mary Meyer, University of Minnesota horticulturist, said earlier this week. "I think we'll have more warm weather. If they're green, continue to water them. I wouldn't give up on tomatoes yet."
Gillman, however, was less optimistic. "We could have a warm week, but unless they're really close, they're not going to ripen," he said. "Try fried green tomatoes."