How to Plant, Grow, and Care for ‘Crimson Sweet’ Watermelons

Craving a taste of pure summer? Join farmer Briana Yablonski to learn all you need to grow delicious 'Crimson Sweet' watermelons.

Slicing into a watermelon during the peak of summer is one of the best ways to give yourself a reprieve from the heat, especially if you’ve just spent a few hours working in the garden. ‘Crimson Sweet’ is a time-tested favorite that yields large, pink-fleshed melons perfect for slicing and sharing with friends.

The plants take over three months to mature, so planting them early in the summer is one key element of growing a successful crop. You’ll also need to supply the proper amount of water, watch out for diseases, and know how to pick a ripe watermelon.

If you’ve never grown watermelons before, don’t be intimidated. I’ll share key growing information as well as helpful tips for growing a successful crop.
What Is It?
‘Crimson Sweet’ is one of the most widely grown watermelons in the United States. It’s what many people think of when they’re looking for a melon for a summer picnic or backyard party: large with a striped green rind and bright pink flesh.

The melon first emerged in 1963 thanks to the efforts of Charlie Hall. Hall developed an interest in botany and plant breeding while attending the University of Arkansas, then went to Kansas State to earn a doctoral degree. While earning his doctorate, he continued to breed watermelons.

After breeding the melons for ten years, he released the ‘Crimson Sweet’ variety in 1963. This cultivar won the All-American Selections award the following year.

Characteristics
‘Crimson Sweet’ has a beautiful and distinctive rind with light and dark green stripes. The melons grow close to a foot in diameter and weigh between 15 and 25 pounds. Slicing into the rind reveals bright pink flesh with an impressive sweetness. The melons aren’t seedless, but they produce fewer seeds than many other watermelon varieties.

The plants have a vining growth habit, so expect them to quickly cover a large section of your garden. Deeply-lobed leaves grow from the vine and remain close to the ground. Eventually, the plants produce small, yellow flowers, some of which are female and others male.

After the female flowers are properly pollinated, they begin producing fruit. The fruits start out small, but quickly grow with a moderate amount of water and lots of sun. You can expect to harvest the first fruits about 85 days after sowing the seeds.

Native Area
Watermelons first emerged in areas of North and Central Africa. The modern varieties of watermelons we’re familiar with barely resemble the native plants and were created after years of plant breeding.

Planting
Like with all melons, you can grow ‘Crimson Sweet’ watermelons by transplanting seedlings or direct sowing the seeds. Either method works well, but transplanting allows you to get a jumpstart on the growing season. Since direct sowing is easier and removes the risk of transplant shock, it’s generally the preferred planting method.

Regardless of whether you want to start seeds indoors for transplanting or sow them directly in your garden, keep a few key points in mind.

First, remember that watermelons are warm-weather crops that require high temperatures to germinate and grow well. The seeds germinate best when the soil is between 80 and 95°F (27-35°C), and germination severely suffers when the soil is below 70°F (21°C). So, wait until the soil warms outdoors, or start the seeds indoors on a heat mat.

Second, bury the seeds at the appropriate depth. Since watermelon seeds are larger than many other types of seeds, you can bury them about one-half of an inch deep.

Finally, plant at the proper spacing. These plants like to sprawl, so allow three feet of space between each plant. You can plant multiple seeds per hole, but thin to one plant once the seedlings have their first set of true leaves.

How to Grow
‘Crimson Sweet’ watermelons are moderately difficult to grow, so don’t be intimidated if you’re a beginner grower. Here are the ideal growing conditions and some care tips.
Maintenance
‘Crimson Sweet’ doesn’t require a ton of maintenance, but it’s important to find a way to manage weeds before your plants cover the ground. Since watermelons sprawl feet in every direction, it’s difficult to walk amongst the plant to pull weeds while avoiding stepping on the vines and leaves.

Adding mulch prior to planting is one of the best ways to limit weed growth. Make sure to pull any large weeds before laying the mulch, or they’ll just grow right through it. You can use organic materials like wood chips and straw, or lay down landscape fabric.

Another piece of maintenance to consider is trellising. Although ‘Crimson Sweet’ grows vines that can work their way up a stake or metal trellis, I don’t recommend training this plant to grow vertically. The large fruits are tough to support and readily break from the vine when they’re suspended in the air.