Watermelons require warm weather and a long growing season to come up with their sweet, juicy flesh. Most watermelon production takes place in the South, but home gardeners all over the United States can grow watermelons. Growing watermelons successfully requires enough space to them and well-drained soil amended with compost or manure. These melons also require hot summers with cold conditions, but growers in the North can also produce watermelons by planting early-maturing varieties.
Because watermelons have been warm-season crops, they cannot withstand a freeze or even a light frost. A air temperature of 33 degrees Fahrenheit or under kills watermelons. The best time to sow watermelon seeds or set out watermelon transplants is just two to three weeks after the last spring frost date. Start watermelon seeds indoors six weeks before spring’s final average frost date. The seeds will germinate in 10 days once the soil temperature is 65 F, but they germinate best when the soil temperature is 95 F.
Extremes in temperatures may influence watermelon growth and development. The finest daytime air temperature for growing watermelons is from 70 to 90 F. Watermelons grown where nighttime temperatures drop below 50 F drop flavor. The plants frequently drop flowers and don’t set fruit when daytime temperatures are 90 F or higher for several days. Watermelons require 65 to 90 frost-free days to develop completely. Air temperatures under 70 F may damage young watermelon plants, slow their increase and reduce their returns.
Production in Cool Areas
Watermelon plant varieties that mature in over 75 days are alternatives in areas that encounter cool summers. Those varieties require a shorter growing season and are often less rampant than other kinds, making them perfect for home gardens. You may grow watermelon plants utilizing transparent plastic as mulch to keep the soil warm and floating row covers to help protect the plants from cool end. Several early-maturing varieties comprise “Golden Crown,” which creates 6-pound, oval melons in around 60 days, and “New Queen,” which creates 5- to 6-pound fruits with few seeds within 63 days.
A watermelon is ripe once you thump it and hear a hallow sound, the tendrils darken where the melon attaches to the stem as well as the melon’s underside is pale yellow. Eliminate a watermelon by cutting, instead of pulling, it from the stem. When recovering watermelons, keep them at a place with a temperature of 50 to 60 F and a humidity of approximately 90 percent. Watermelons saved for several days in a temperature below 41 F may suffer chilling injury. Eat watermelons as soon as possible after they’re harvested because they lose color and crispness when stored for long periods.