Tomatoes

Tomato ‘Native Sun’

In choosing which tomato varieties to offer each year, we try to cover all the bases, including disease resistance, exceptional flavor, a wide range of flavor profiles, sizes, colors and culinary uses, heat-tolerance, cold-tolerance, early maturation, and adaptation to what we’ve known as ‘Colorado conditions’. This year, ‘Colorado conditions’ have changed.

Though their leaves may wilt midday, tomato plants can endure 100°F temperatures. But fruit set often stops above 85°F during the day and especially if night-time temperatures are above 75°F. This is because because pollen is less viable at higher temperatures. This causes ‘blossom drop’, when flowers fall off instead of turning into tomatoes (by the way – tomato flowers are self-pollinating, with pollination occurring before flowers open. Once open, they may be visited by bees, especially bumblebees). Metabolism slows, and growth slows. Plants focus their energy on self-preservation instead of fruit production.

Gardeners need to be aware that containers and raised beds heat up faster than in-ground soil. Some tomato varieties can handle the extra heat to their roots better than others. Heat-resistant varieties are able to continue setting fruit into the mid-90°F range and even to 100°F. It helps if nights cool down to below 75°F.

Now that the heat is on, take note of which tomatoes in your garden are fruiting successfully this year. If the varieties that are successful for you are not on the following list, please let us know about them! Email staff@harlequininsgardens.com.

For heat tolerance, these varieties are recommended:
Native Sun, Super Sioux (aka Super Lakota), Sun Gold, Matt’s Wild Cherry, Burrell’s Special, Floradade, Maglia Rosa, San Marzano, Mexico Midget, Stupice, Thessaloniki, Cherokee Purple, Bella Rosa, Black Krim, Green Zebra, Sweet 100, Beam’s Yellow Pear, Principe Borghese, Early
Girl, Coyote. This list will grow with your input!