Over at least 5,000 years, the watermelon has transformed from a bitter fruit with hard, pale-green flesh into the omnipresent picnic-table companion.
Originating from Northeast Africa, watermelon paintings can be seen on various Egyptian tombs. One illustration shows an oblong watermelon, which is different than the wild type (Citrullus lanatus var. Colocynthoides). This indicates the ancient Egyptians were selective breeding them.
Initially, people ate the seeds and discarded the flesh. Acting as a natural canteen, they could store them for weeks to months, unlike other fruits, and extract the water.
Deceased pharaohs had watermelons placed in their tombs to help them mollify their thirst on the long journey to the afterlife. Eventually, farmers would start cultivating watermelons for taste in addition to the ability to save water.
By A.D. 300, watermelons were sweet enough to make it on the dessert menu. The gene for the sugar content is paired with the red color in watermelons. Around this time, the melon’s color intensified from yellow to the colors we recognize today.
Get Growin’
A few years ago, I was running out of room in my raised-bed vegetable gardens for space hogs, such as watermelons and squashes. So I took to my front yard.
In the center of my grass lawn, I created a miniature hill of compost. I planted a half dozen watermelon seeds and thinned them to three plants. The vines rambled all over my sloping yard. It was beautiful.
If you have a very short warm growing season, start with small transplants. Watermelons need at least 80 days of warm weather with the soil at 70 degrees Fahrenheit or warmer.
You can start seeds indoors or in a greenhouse only two to three weeks before planting, as larger plants don’t transplant well. If you are seeding directly into the ground, sow seeds 1 inch deep and keep the soil damp until germination. Plants should be 3 to 5 feet apart.
Need a watermelon you can grow in a container? Check out the sugar pot!
Watering Watermelon
Watermelon plants need water to thrive. Thankfully, they have deep taproots and watering is rarely necessary unless you experience drought conditions.
The Desert King heirloom variety has been bred to handle the heat and arid conditions of Arkansas. Seeds and seedlings need quite a bit of water to get it started. Vines are most vulnerable to drought during planting to fruit.
Mulching around the vines will help conserve water. Using drip irrigation or soaker houses will prevent the foliage from getting wet and will help prevent fungal diseases. As the watermelons start to mature, withholding water will increase their flavor.
Watermelons and their kin are susceptible to cucumber beetles and vine borers. Applying an insecticide in Tampa, Florida, where I live, is required if I am going to harvest any fruit. After the melons have reached 4 inches in diameter, place them on cardboard or a layer of straw to protect them from pests. 
Water You Waiting For?
Although almost 300 varieties of watermelon are grown in the U.S. and Mexico, only about 50 are popular with farm stands and supermarkets. To diversity your garden, add these heirlooms to your spring planting.
Ali Baba
Baker Creek Heirloom Seeds acquired these seeds from Aziz Nael, an Iraqi who collected this variety more than 12 years ago in his homeland. They are resistant to sun-burning due to their light color. The plant produces heavy yields of oblong fruit. Size at harvest: 12 to 30 pounds
Art Combe’s Ancient
Art Combe, a Southwestern plant expert, found seeds in an abandoned sandstone cave in Arizona in the early 1920s. After decades of selective breeding for flavor and size, this Native American variety is now available for everyone to enjoy. 20 pounds
Beni Kodama
This miniature melon is one of the earliest maturing melons and is perfect for short seasons. 2 to 3 pounds
Blacktail Mountain
Developed by Glenn Drowns, owner of the Sand Hill Preservation Center in Iowa, this melon produces a sweet, red flesh. 8 to 12 pounds
Read 6 tips for growing the most delicious watermelons ever!
Desert King
This watermelon is one of the most drought-tolerant varieties. It produces a chartreuse rind and yellow flesh, and it has the ability to store for long periods of time, making it very popular in the watermelon-growing areas of Arkansas. 20 pounds
Georgia Rattlesnake
Dating back to the 1830s, this striped melon has a sweet-tasting, light-colored flesh. It also ships well. 25 to 30 pounds
Kaho
This heirloom was brought to Japan from China in 1912. Fruits are oblong with a thin rind and orange flesh. 2 to 4 pounds
Moon and Stars Yellow Flesh
In addition to the fruit’s beautiful pattern, the leaves are also speckled in yellow. Spots can range from tiny to several inches across. 40 pounds
Orangeglo
Deep-orange flesh that has an almost tropical flavor, it’s resistant to wilt and insects. 20 to 25 pounds
Otome
This Japanese variety is ideal for short growing seasons. Fruits have light green skin and salmon-rose flesh, which is supersweet. 3 to 4 pounds
Royal Golden
When ripe, the rind turns gold. 8 to 25 pounds
Strawberry
Fine-grained strawberry colored flesh, with almost no seeds, this super sweet fruit is moderately disease-resistant. 15 to 25 pounds
Sugar Baby Bush
Vines only reach 3 1/2 feet in length! 6 to 12 pounds
Recipes
Of course, there is nothing wrong about just eating your watermelon in slices. But there are other ways to enjoy this summer staple. Try soup, sorbet, salsa, skewered or quick pickled!
Watermelon Soup
Gazpacho, a classic of Spanish cuisine, is a cold soup made of raw, blended vegetables. It’s wonderful with watermelon.
Ingredients
- 1 large tomato, pureed
- 1/2 serrano chile
- 2 cups watermelon, cubed
- 1 teaspoon red wine vinegar
- 1/4 cup extra-virgin olive oil
- 2 tablespoons minced red onion
- 1/2 cucumber, seeded and minced
- 2 tablespoons minced fresh dill, plus more for garnish
- Kosher salt and freshly ground black pepper
- 1/4 cup feta cheese, crumbled
Puree tomatoes, chile, onion, cucumber, dill and half of the watermelon. Mix in the red wine vinegar and olive oil, and pulse. Puree until smooth. Pour into chilled bowls, and top with dill, feta and the remaining watermelon cubes.
Watermelon Sorbet
We all know that cold watermelon from the refrigerator is great. Try it frozen.
Ingredients
- 3 cups watermelon, cubed
- 1 cup lemon-lime soda
- 1/4 cup sugar
Blend all ingredients until smooth. Chill in freezer overnight. Thaw for 10 minutes and serve.
Watermelon Salsa
Forget tomato-based salsa! For this recipe, use sweet watermelon from your summer garden.
Ingredients
- 3 cups watermelon, cubed
- 1/2 cup cucumber, diced
- 1/2 cup yellow, orange or green peppers, diced
- 1/4 cup red onion, diced
- 1/4 cup parsley, chopped
- 2 to 3 tablespoons jalapeños, diced and seeded
- 2 tablespoons lime juice
Combine all ingredients in a large bowl, and enjoy with chips.
Watermelon Skewers
This makes a great appetizer or party snack.
Ingredients
- 3 cups watermelon, cubed
- 1 pint of tomatoes
- 8 ounces feta cheese
- 2 1/2 tablespoons fresh lime juice
- 1 tablespoon olive oil
- mint as garnish
Gently toss ingredients together, and chill for 1 hour in refrigerator. Arrange on skewers.
Watermelon Rind Quick Pickles
Yep, you read that right: quick pickles with watemelon rinds!
Ingredients
- watermelon rinds
- 2 cups of water
- 2 cups of apple cider vinegar
- 3 cups of white sugar
- 1/2 teaspoon whole black peppercorns
- 1/2 teaspoon whole cloves
- 1 tablespoon Kosher salt
- 2 teaspoons coriander seeds
- 1 teaspoon celery seeds
- 1/2 teaspoon crushed red pepper flakes
- 1 cinnamon stick
Remove most of the flesh from the rind. Peel and discard the dark skin from the rind. Bring ingredients to boil. Gently place the peeled rinds into the pickle juice. Add in small batches so the rinds can be submerged.
Once it resumes boiling, boil for 3 minutes. Place rinds in Mason jars. Fill jar with liquid. Once cool, refrigerate for 3 days and enjoy.
Figuring out when a watermelon is ripe can be tricky. Some farmers say to watch the tendrils closest to the fruit. When they dry up and brown, the thinking was that the melon was ready. However, some of these heirloom and hybrid tendrils dry up much sooner than optimal ripeness.
The best way to tell if your melons are ready is to check for the spot where the melon was sitting. If it turns from white to bright yellow, it’s ready. The top rind will change from bright green to dull as it matures.
Sidebar: Seedless Wonders
Can you recall your middle school biology class? I do! I teach it every day.
Seedless watermelons are sterile hybrids, just like a mule. To get more mules, you need more horses and donkeys. To get more seedless watermelons, you need to cross male pollen that contains 22 chromosomes per cell (standard amount) with a female flower that has 44 chromosomes.
When you plant those seeds, the fruit will mature. But the inside won’t contain any viable black watermelon seeds, only small white seed coats, which are edible.
To get a female flower to have double the number of chromosomes of a typical watermelon, scientists treat them with colchicine. This chemical is derived from a crocus.
If you think seedless watermelons taste blander than those with seeds, it’s your imagination. They have the same genes as their seeded siblings, and have three sets instead of two.
This article originally appeared in the March/April 2020 issue of Hobby Farms magazine.
