Soil temperature is an important factor in deciding when to sow vegetables. The optimal temperature for your vegetables is between 32 and 40 degrees Fahrenheit, depending on the vegetable. Of course, if the temperature is too high or too low, lettuce seeds will fail to germinate. A tomato plant grows well with the right amount of sunlight and heat. But what happens when temperatures dip toward the freezing mark? In most cases, however, commercially cultivated plants will thrive in temperatures ranging from 59-86°F. After germination, the ideal temperature for growing lettuce is 55 to 65 degrees Fahrenheit (13 to 18 degrees Celsius). According the North Carolina State University Extension, lettuce will start to bolt (flower and make seeds) at daytime temperatures of 70 to 80 degrees Fahrenheit (21 to 27 degrees Celsius). Try setting the refrigerator section temp to medium or the number 5. Although Anna must grow lettuce indoors or in a heated greenhouse in her extreme conditions, gardeners on this panel in warmer climes can successfully grow lettuce in a cold frame or low tunnel. Missouri State lists lettuce under the category of “hard frost hardy,” which means it can withstand frosts below 28 degrees. You can combine two or more of these methods to keep your lettuce even cooler and extend the season to enjoy a longer harvest. Excess heat or cold may inactive essential enzymes required for ripening to progress or cause temperature injury, resulting in permanent loss of eating quality. "If your refrigerator is too cold, your greens could freeze and die. 3) Products sensitive to ethylene should not be stored together with products producing ethylene. … The temperature control thermostat directs voltage to the compressor, evaporator fan motor, and condenser fan motor (if applicable). If these same broccoli plants had experienced cool weather, they would probably survive the sudden cold. However, the leaves of lettuce will become bitter after the plant has bolted, to the point where the leaves will be inedible. This appears as a darkened t… By continuing to browse you consent to our use of cookies. Does boiling water kill seeds? I've noticed that there are differences in temperature inside the fridge. The best soil temperature for lettuce germination is 60 to 86 degrees Fahrenheit (16 to 30 degrees Celsius). The heavier row cover fabrics can protect your crops for up to 6 to 8 degrees. See this chart of soil temperature conditions for vegetable seed germination provided by the Alabama Extension System. One solution is a refrigerator thermometer. learn more about Magenta lettuce from Johnny’s Selected Seeds. Too much moisture can cause fruits and vegetables to go bad quickly. What happens when seedlings get too cold? Enjoy! You need to know the right time to grow them. Experts agree that the ideal water temperature for hydroponics is the same as the nutrient solution temperature. 20°F (-7°C): Some beets, broccoli heads (maybe OK to 15F), some cabbage heads (the insides may still be good even if the outer leaves are damaged), celeriac, celtuce (stem lettuce), some head lettuce, some mustards/Asian greens (Tendergreen, Tyfon Holland greens), radishes, most turnips with mulch to protect them (Noir d’Hiver is the most cold-tolerant variety).Large oat plants will get … You can also make a cloche out of wire (such as chicken or rabbit wire), although this will not provide cold protection by itself. How long do seeds last? We’ve measured temperatures of 10°C and more in some fridges. Preparing your garden soil is one of the biggest factors... link to What Are Dwarf Fruit Trees? Sustained double-digit temperatures allow heat-loving bacteria to thrive, potentially threatening the safety of your meat and fish. You can learn more about lean-to trellises and other designs in my article here. If the temperature control thermostat is not working properly, it may cause the refrigerant system to run longer than necessary. However, it also means that the lettuce leaves will become bitter, to the point where most people would not enjoy eating them. As an added bonus, shade cloth can protect lettuce from birds. If frost is predicted for several nights but the days are sunny, fill the containers with water and wrap them in black garbage bags. Is 42 degrees too cold for seedlings? Plant a few seeds every week and you'll have a constant crop for fresh salads . How cold is too cold for chickens? Most seeds will germinate over quite a wide range of soil temperatures but the speed of germination will vary. If these same broccoli plants had experienced cool weather, they would probably survive the sudden cold. 34-38 degrees F ( 4 degrees C ) or colder your yard the sun and warms up the temperature your... 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