This is likely towards the end of the season, as fall frosts approach. But when spring comes, we are eager to get our gardens planted, and we don't want to wait around until midsummer to plant beans. the USDA plant hardiness zone map will tell you what zone you are in. The most basic way to use a row cover is to simply drape them over your plants. What Temperatures Cause Frost Damage? At 40 degrees Fahrenheit or lower, tomato plants will sustain chilling injury after prolonged exposure. There’s the best temperature for germination and then another best temperature for growing. In some cases, you would like to move your seedlings outdoors a little sooner. The goal here is to briefly expose them to cooler temperatures than they would like (not freezing or damaging temperatures!). It starts at the beginning of the season, with choosing the right tomato varieties. You can also see my illustration of ideal temperature ranges for tomato plants here. At What Temperature Should You Cover Tomato Plants? Lower temperatures will prevent the tomato plant … Front Range tomatoes often get a late start due to cold night temperatures that can last into the second week of June. These plants can take several weeks to recover and resume active growth. If the temperature is cool, but clouds are visible, your plants may be protected. A freeze or frost is when the nighttime temperature is between 28-32 degrees F. There’s also what’s known as a hard or killing frost which is more severe. Does your lettuce need to be protected from frost? learn more about hardening off seedlings in my article here. Row covers are great because they can protect your plants from pests at the same time that they protect from cold. Always remember to watch for frost in the weather forecast! The cap on the top part of the gallon container will act as the vent. Now, let’s assume I want to move the seedlings outside 3 weeks (3*7 = 21 days) after the last frost date. Watch the weather forecast often. This is sometimes called a low-tunnel or high-tunnel (depending on the height), and it is a good alternative to cloches for younger plants. check out my article on when it is too late to plant tomatoes. The only drawback is that cold tolerant and fast-maturing tomato varieties tend to have smaller fruit. Growing Temperatures for Tomatoes Tomatoes can tolerate a night time temperature falling to 13.5ºC but if the daytime temperature falls below 15ºC for a week … There are plenty of alternatives to wood mulch. Some cold frames open automatically when the temperature gets high enough, and then close again when it gets low enough. In either situation, a cold frame will help. Cool soil stunts plant growth and prevents root development. Tiffany Selvey has been a writer since 2007. According to Penn State University, flowers may also drop off of the tomato plant. According to the University of Illinois Extension, the texture and flavor of the fruit will decline at these temperature. Let’s assume four weeks’ worth of harvest for my tomatoes (28 days). This will require the use of protective measures, such as row covers (more on this later). © Copyright 2020 Hearst Communications, Inc. If you live in Jacksonville, Florida, you can plant now. However, nature may have something different planned. Additionally, boiled water can be effective against coronavirus. The effects include stunted growth of plants, wilting of leaves, and pitting of fruit. You have two choices to bypass this limitation: For the second option, the question is: when should you start the seeds? When cold threatens 68° - 78° degrees Fahrenheit ) at night is critical during pollination with... State University, flowers may also drop off of the gallon container will as! Will tell you what zone you are in several weeks to recover and active. 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