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How to Grow Seedless Watermelons

How wonderful would it be to sink your teeth into a juicy piece of watermelon, without having to worry about biting into its seeds? We explain how to grow seedless watermelons in no time, that are just as tasty as the ones with seeds.
Gardenerdy Staff
Seedless watermelons are created without modifying their genetic make-up in any way, by crossing the male pollen of a watermelon with 22 chromosomes per cell, with a female watermelon that contains 44. After it matures, the white seeds from within contain 33 chromosomes that stop producing seeds, thus turning it from a diploid watermelon, into a triploid.
Seedless Watermelon Hybrid: Explained
To halt seed production, it is essential to increase the number of chromosome sets to four. The process of making the chromosomes double in number is done by introducing the drug colchicine, into the plant―this substance stunts the segregation of chromosomes during meiosis. The plant which is formed as a result of this, is known as a tetraploid plant. It takes about five weeks for a triploid (the actual product) to take form. Because triploids unfortunately cannot reproduce sexually, they are planted next to diploid plants that produce pollen, making it easy for pollen to be transported to the triploid plant by insects or birds; this process is necessary to see the end result take shape.
Ideal Climatic Conditions
To grow seedless watermelons, the temperature needs to be maintained at 95° F during the day, and 70° F during nightfall. The temperature needs to be monitored because the watermelons won't grow as desired.
Proper Planting and Watering
According to the experts, the soil temperature should not be less than 70° F, in order to promote germination. You should ideally plant two seeds per pellet; these must be soaked and drained before the actual sowing is done. When the seedlings emerge, one must water them moderately and not douse them; the soil should be moist but not saturated with water. The required pH of the soil is 7. You will be required to get your planting area ready at least three weeks before it can actually be planted.
The area should have compost spread on the soil with granite dust/green sand sprinkled over it. There should also be a black plastic sheet over the bed with a 12-inch opening. The distance between two plants will determine its outcome, so plant them at least 3-6 feet away from one another. To achieve a batch of ripe, succulent watermelons, you can place them on a light-reflecting sheet of foil to help speed up the process; the extra heat allows the watermelons to ripen sooner. Use drip irrigation or soaker hoses to water the plants.
Successful Pollination
The result of improper pollination will leave you with a bad batch of seedless watermelons, that lack texture and flavor. As per the statistics, the number of pollinating insects should be about 15,000 per acre in the area where these are grown. Among the insects, the presence of honeybees is vital. Every row of diploid pollinators should be followed by two rows of triploid plants for effective pollination.
To check if a seedless watermelon is ripe, inspect if the two tendrils near the fruit are dry. To keep ripening seedless watermelons safe, don't let them directly touch the soil, for fear of being attacked by pesky visitors. Any fluctuations in temperature will leave your watermelons struggling against a disease's effects. Therefore, maintaining the aforementioned numbers is vital. Check on the watermelons as often as possible and take care of any disease-related issues as and when they occur. Also, avoid extracting the vines that grow around the watermelon, since this is where it obtains its sweetness. It will in no way help in the ripening process, so avoid getting rid of the vine shoots.