Temperature is key when it comes to getting seeds to germinate. Pepper seeds require the right combination of heat and dampness to get the growing process started. Cold temperatures slow germination and, when too cold, will prevent germination from happening at all. But too hot isn't good either or the seeds will fail to grow. When growing peppers from seed, picking the optimum temperature makes for healthy, vigorous seedlings and plants.
Temperature Range and Optimum Temperature
Seed packages list the temperature range for germination along with the optimum temperature. The range indicates the temperatures at which pepper seeds will germinate. The optimum temperature indicates the ideal point within that range for rapid germination and greatest seed germination success. When pepper seeds are planted in soil that is within the temperature range, but cooler or warmer than the optimum temperature, the seeds take longer to germinate and fewer will sprout successfully.
Germination Temperature for Peppers
Pepper seeds require a temperature range between 65 and 95 degrees Fahrenheit. The optimum temperature for germination is 85 degrees Fahrenheit. At the optimum temperature, pepper seeds germinate and sprout within eight days. The best way to control soil temperature when planting pepper seeds is to use a seed starting flat and a heating pad. Heating pads go under the seed flat and can be adjusted to provide bottom heat and keep the soil consistently at the ideal temperature.
Heat and a long growing season are key for growing peppers successfully. The best way to get an early start on the growing season is to start the seeds indoors six weeks before transplanting them outside. As soon as the soil temperature in the garden reaches 75 degrees Fahrenheit and night temperatures are consistently above 60 degrees Fahrenheit, pepper seedlings are ready to go in the ground. A soil thermometer is a useful tool to determine soil temperature.
Once the seedlings are planted outdoors, peppers need a growing season of 110 to 150 days. Their color develops when growing temperatures are 60 to 75 degrees Fahrenheit. If temperatures drop below 50 degrees Fahrenheit, peppers will not ripen successfully.
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