How to Grow Tomatoes When the Temperature is Over 105?

Tomatoes are a heat and sun-loving plant, but when the weather turns exceptionally hot and dry they suffer just like many other plants do. Growing tomatoes in hot temperatures requires you to be proactive in protecting them. You must ensure they continue to receive all the moisture and nutrients they need to produce a healthy harvest. A single day of temperatures 105 degrees Fahrenheit or higher is most likely not harmful, but more than that may damage the plants if care isn't taken to protect them.

Difficulty: Moderately Easy

Instructions

Things You'll Need:

• Mulch
• Black plastic
• Cheese cloth
• Wooden posts
• Staple gun

1. Apply a 3-inch layer of organic mulch around each tomato plant to preserve soil moisture during hot weather. Alternately, lay black plastic mulch over the garden bed and cover with a 1-inch layer of organic mulch.

2. Check moisture in the soil daily when temperatures are above 90 degrees F. Supply at least 2 inches of water a week or enough to keep the soil moist but not soggy.

3. Shade plants during the afternoon to prevent sunscald, which turns tomato skin leathery and causes the fruit to rot. Drape the plants with cheesecloth or staple cheesecloth to two wooden posts and place in the ground in front of the tomato bed in the afternoon to provide shade.

4. Pick full-sized fruit that isn't yet ripe if daytime temperatures are above 100 degrees F for more than three to four days. Bring the fruit inside to finish ripening.

5. Avoid feeding the plants with fertilizer during intense heat. Wait until the temperatures cool before resuming fertilizer treatments. Feeding during adverse conditions may kill the plants.

Tips & Warnings

• Blossom drop occurs when the plants are blossoming during intense heat. Keep the plant well watered and healthy, and it will produce new blossoms once temperatures cool.
• Tomatoes stay orange when temperatures are above 95 degrees F, but will turn red if brought inside to ripen.
• Plant heat-tolerant tomato varieties instead of the standard varieties if summer heat is an issue in your area.
• Water is the most important thing during hot weather. Lack of moisture may cause the fruit to "catface" or split once moisture levels return to normal, ruining the fruit.

References

• Kansas State University Extension
• University of Illinois Extension