How Late Is Too Late To Plant Tomatoes?

If you planted your tomatoes early in the season, chances are the harvest is winding down as the summer heat increases. The good news is that you can still plant tomatoes for a fall harvest, but it will depend on the tomato variety you plant and the region in which you're growing. 

Determinate bush and cherry tomato varieties grow quickly and can still be planted in late July. Since determinate tomatoes produce fruit earlier and all at the same time, they are best for growing during a short season. This tip is also handy in regions with exceedingly hot summers, as you can plant them early and harvest everything before the high temperatures prevent the plants from setting fruit.

The key for planting late tomatoes for a fall harvest is to source healthy plants from your local nursery, which might offer varieties suited to your area, rather than sowing from seed, as this will not work so late in the season — with few exceptions. It's also important that you pay attention to your specific growing region's temperatures and sunlight levels, to determine when it's too late to plant tomatoes for a successful harvest.

Among the many types of tomatoes, common varieties like "Early Girl," "Fourth of July," and "Sungold" take 50 to 62 days to mature, compared to 65 to 80 days for long-season varieties. So if you plant now, you'll still be able to harvest some fruit, even as far as zone 3, before temperatures get too cold. Also, look for varieties labeled "patio," which are tomatoes that can be grown in containers and indoors or move into a greenhouse if an early frost is in the forecast. 

Just like there are heat-resistant tomatoes that grow well in hot climates, there are certain short-season varieties which have been developed to thrive in cooler temperatures, producing large harvests before the first frost. Cold-resistant tomatoes often have names that identify them as such, like "Red Siberian," "Polar Beauty," and "Northern Exposure." All of these are ready for harvest in less than 70 days. Oregon State University's vegetable breeding program has developed tomato varieties that thrive in their cold, wet climate, like "Oregon Spring" and "Gold Nugget."

There are two tomato varieties that are even faster. "Sub-Arctic Plenty,"  often marketed as "Chilly Willie," takes only 42 days to mature, while "Quedlinburger Frühe Liebe," a German heirloom tomato, ripens in just 40 days, which is unusual for an indeterminate variety. Both of these will give you tomatoes much earlier and much later in the season. Another variety perfect for late planting is "Coldset," which will germinate at lower temperatures and might even tolerate a very light frost. They will grow well as long as the soil temperature remains above 65 degrees Fahrenheit.

These tomato varieties are ideal for gardens where the summer season is short and the fruit doesn't have enough warm sunny days to fully ripen. It's also worth noting that you can harvest tomatoes when they're still partially green, so you could potentially harvest some of these fast-growing varieties in 30 to 35 days and let them ripen on the kitchen counter. Worse case scenario, you can use the green tomatoes to make chutneys, salsas, jams, or simply make some classic fried green tomatoes.