This time of year, watermelon is a treat. Everybody has a favorite way to eat watermelon. Mine is to put it in the fridge to get it nice and cold, cut it up in slices, and put a little salt on each bite as you eat it. If you don’t have a fridge around a cold creek is a good alternative. But, if you accidentally pick a watermelon that’s not all the way ripe, it might be a bummer once you cut it open. With the 4th of July coming I thought I would talk about how to select a ripe watermelon.
Watermelon requires a lot of heat to be able to grow. That means that watermelon grown in the mountains won’t be ripe in time for the 4th of July. There are smaller varieties that don’t take as long to grow. Typically, watermelon take 70-90 days to be ready to harvest. If you are planting your own watermelon it’s typically easier to start them from transplants, but you can start your own seeds. Watermelon plants will need 8 feet of space on each side.
If you are picking watermelon off the vine you want to look at the curly tendril that is on the stem closest to where it meets the fruit. When you see that curly tendril dry up and turn brown the watermelon is ripe and ready to harvest.
If you are looking at watermelon that has already been picked there are a couple of tricks that you can use so that you look will a pro and WOW onlookers at the grocery store or market. You can thump a watermelon to gauge its ripeness. A ripe watermelon will have more of hollow thud sound to it. An unripe watermelon will have a higher pitched, less hollow sound to it. It’s usually best to thump multiple melons with this approach to really be able to gauge the ripeness. Another approach is the check the ground spot. This is just the spot where the watermelon sat on the ground. If it has a creamy yellow or buttery white color then it is ripe. If the ground spot is plain white then it’s not ripe yet.
As watermelon ripen the green color will start to dull. So, if the watermelon still has a sharp green hue, it’s probably not ripe. If you are picking a striped watermelon this method is particularly useful. Another tip is to pick up two watermelons of similar size. The heavier one is riper. Be careful using this tip because if it is too heavy, then it’s overripe.
A whole watermelon will stay ripe for about 2 weeks if its stored below 60 degrees. At run temperature it will last for about 10 days.
Seedless watermelon is very popular and make up 92% of watermelon sales in the US. Seedless watermelon is not genetically modified, rather it is how they are bred that makes them seedless. Some watermelon is diploid, which means they have 2 sets of chromosomes. Other watermelons are tetraploid, which means they have 4 sets of their chromosomes. When plant breeders cross pollinate a diploid with a tetraploid it creates a watermelon that produces a seed that are triploid. Those triploid seeds are planted to make seedless watermelon. Triploid watermelons are sterile. It’s a similar concept breeding a mule, which is a cross between a horse and a donkey. These seedless watermelons might still produce a few seeds, but they won’t mature and turn black.
If you have questions about watermelon contact your County Extension Office or send me an email at Jacob.Williams@uga.edu.