Skip to Content

How to Grow Watermelon

No summer is quite complete without the sweet taste of watermelon folded between the pages of one timeless memory and the next. If you’re getting tired of hunting for these delicious melons at the grocery store and want to learn how to grow watermelon right in your own backyard to enjoy all season long, we have got you covered!

Closeup of a watermelon on the vine.
Growing watermelon isn’t as hard as you might think!

Read on to learn all there is to know about how to grow watermelon—from choosing the right spot, to planting and caring for your watermelons, to serving them up and enjoying them when the time comes.

Selecting a Location

One of the most important things to bear in mind when it comes to learning how to grow watermelon is to start at the source. Where and when you plant your watermelons will play a key role in how well they flourish, so the importance of this step can never be overlooked!

Young watermelon leaves in the sun. Knowing how to grow watermelon begins with selecting the proper growing site.
Young watermelon plant leaves.

Watermelons can be quite the fickle and particular growers, demanding a specific and very narrow pH balance in their soil in order to thrive. Watermelon seeds or young transplants should be placed into a well-drained, sandy soil mixture with a pH level balanced between 6.0 and 6.5; you can determine these pH levels ahead of time and whether you are already in that range by testing your soil’s natural balance before you add any compost or fertilizers to it, both of which will affect the pH levels.

Because watermelons are a vining melon, they also need plenty of room to spread out! Particularly if you have multiple plants in your garden—and more than one watermelon plant or other melon variety—you will want to make sure your watermelon plants have either a good span to spread their vines into (a space of at least 2 feet), or proper trellising to encourage upward growth. Because they can be trellised, watermelons can be grown even in small gardens, though you may have to consider just a single plant due to space constraints.

Watermelon vines trellised to grow vertically.
Trellised watermelon vines.

Last, but certainly not least, most watermelon varieties thrive best in warm temperatures—though they can survive temperatures as cold as 33 degrees in small doses, usually 80 degrees Fahrenheit or above is ideal for their maximum maturity. So you will want to ensure you plant your watermelon plants in direct sunlight and away from any risk of frost.

How to Grow Watermelon From Seed

Not only is it important to know how to grow watermelon from seed, it is also worth mentioning that this is the most highly recommended way to approach how to grow watermelon plants in general. Watermelons thrive much more on direct planting than transplanting, with significantly greater and speedier growth rates overall when compared to transplants that are started indoors even as much as 6 to 8 weeks earlier.

Newly sprouted watermelon seedlings in a garden.

With all of this in mind, the biggest key to growing watermelon right from the seed is to make sure you start once the soil temperature is consistently above 65 degrees Fahrenheit and the threat of frost has passed. At this point, you can then place the seeds in holes roughly ½ to 1 inch deep and group 2 to 3 seeds in each of these holes, spaced roughly 2 feet apart to allow for the eventual vines to spread.

Pruning your watermelon seed patches will be critical further down the line; once you have some established watermelon plants, you can choose which one is thriving the most heartily and remove the other one or two plants from that seed group, allowing the soil to concentrate its resources into that single thriving plant.

How to Grow Watermelon From Transplant

Although, as stated above, it is always preferable to grow watermelon plants from seed, that does not mean this is always possible. For watermelon growers living in a cooler overall climate, such as in the northern hemisphere, you may have little choice but to begin your watermelon seeds indoors, so you will want to know how to grow watermelon plants from transplant the absolute best way in order to give them the best chance as prospering and thriving.

A starter tray of watermelon seedlings.

With a view toward helping your seedlings along, it is recommended to invest in an indoor growing method when starting these seeds that will minimize how much the roots are disturbed during future transplanting. Some favored methods are to use newspaper pots or soil blocking for the seedlings.

Another critical element for growing watermelon plants from indoor transplants is to not start them too early, as they will suffer more when transplanted as larger plants; all of this delicacy is due to the fragility and intricacy of the watermelon plant’s roots, which can have difficulty if disturbed once they’ve set in. For this reason, you will want to start about 6 to 8 weeks prior to the date of your typical final frost.

Once seedlings are planted in your degradable planter or pot of choice, they should be placed in direct sunlight or beneath a grow light and kept consistently warm. After they have begun to germinate, and once the outdoor soil temperature is consistently high and air temperature reaches above 50 degrees Fahrenheit for a consistent period as well, you can transplant your watermelon seedlings into holes dug roughly 2 feet apart at a depth of ½ to 1 inch deep.

Watermelon Care

Watering

As with any vining plant, one of the tricks to learn in how to grow watermelon plants that remain happy is to understand the delicate balance water plays in their growth. Watermelons require a fair bit of water for the sake of both the plant and the vines’ overall health and the juiciness of the fruit itself.

A woman uncovering a watermelon in the garden.

For this reason, you should water your watermelon plant’s vines early in the morning to allow time for both absorption of vital water into the vines as well as evaporation of residual dampness during the warmest hours of the day. This method will help prevent fungal diseases that can grow on damp leaves and other saturated foliage.

As for the soil itself, watermelon plants thrive on about 1 to 2 inches of water per week. The soil should remain damp up to this depth, but not saturated. On particularly scorching days or during a heat wave, you may find that the soil up to 2 inches deep has grown dry, in which case it is encouraged for you to water your watermelon plants a bit more frequently to maintain proper growth.

Remember to always water your watermelon plant at the soil line, not from above, as overhead watering raises the risk of fungal diseases from water lingering too long on the leaves and vines.

Fertilizing and Feeding

Knowing how to fertilize and feed your watermelon plant properly is another key component of growing watermelon plants that will produce a bumper crop of sweet and delicious melons.

A watermelon on the vine in a garden.

Because watermelon plants are known to be heavy feeders, this requires your soil to have plenty of organic matter available even before planting; one way to encourage this is by laying down a slow-releasing, organic fertilizer when you are first preparing your garden patch for planting during the season. You can then add a layer of compost to the garden around the middle of the season to help aid in the continued and steady growth of your watermelons.

When it comes to food for your watermelon plants, consider a fish emulsion or other organic feed. Some brands offer these specific to vining plants.

How to Troubleshoot Watermelon Problems

Once you are confident in how to grow watermelon, you will want to learn all the important factors to protect your crop. Let’s break down some of the top three watermelon problems and resources on how to address them.

Watermelon Pests

Knowing the kind of opposition you are up against is an important part of learning how to grow watermelon plants that can endure the elements. Two of the greatest natural pests to a watermelon crop are cucumber beetles and aphids. These tiny little garden antagonists can pack a real damaging punch to your harvest, so it is best to be on the offensive and prevent them before they ever strike.

Closeup of a grasshopper on a stalk.
Grasshoppers are a common watermelon pest.

Because cucumber beetles are disease spreaders and can make their debut on the scene as early as during the seedling stage, consider laying down a floating row cover that can protect the seedlings from cucumber beetles and their diseases until the time comes for blooming. At this point, the floating cover should be removed to encourage visits from pollinating insects.

Once your watermelon has set its fruits, you may also consider investing in a commercial melon cradle or creating one of your own out of carboard; this will keep the fruit off the ground, which can protect it from some pests as well as from certain diseases.

Weeds

Weeds can be a nuisance in any garden, and mulching your watermelon plants is key to growing watermelon plants that will withstand lots of these issues, as well as helping to decrease the number of times you have to water due to better moisture retention in the soil.

Mulching down at the base of the plant and outward beneath the vines will help keep weeds at bay and keep the soil moister for longer; this can also add a layer of protection between the melons themselves and the damp ground, which in some cases will decrease the risk of blossom end rot.

Watermelon Diseases

Another common trial that stands in the way of many a gardener learning how to grow watermelon plants in a happy and healthy environment is learning about what can make that environment less than ideal.

Watermelon leaves showing symptoms of powdery mildew.
Watermelon leaves showing signs of powdery mildew.

Some of the common diseases that can plague a watermelon crop are powdery mildew, downy mildew, and blossom end rot. To learn more about these and other disease that can threaten your watermelon crop—and how to address them—check out our article on How to Treat 7 Deadly Watermelon Diseases.

Preparing and Serving Watermelons

There is an abundance of ways to enjoy watermelons, which is a good thing when you are planting lots of them and using the tips in this guide to help them produce a fantastic crop!

Closeup of a salad with watermelon and arugula.

Besides the most obvious method of enjoying a watermelon, which is simply as a raw and delicious snack, you can prepare and serve it in other ways. Among the most popular uses for watermelon are in fruit juices and smoothies, and even in certain alcoholic beverages as either a flavorful component or garnish.

Additionally, you will often find watermelons as a staple in a fruit salad and even as a component to certain cakes and cupcakes!

Two glasses of watermelon smoothie.

Many parents also find that cubed and frozen watermelon popped into a silicone or mesh teether makes for a great snack for little ones who are cutting teeth. Kiwi pairs great with watermelon in this recipe for popsicles.

Watermelon is also finding its way into savory dishes such as balsamic glazed chicken recipes; and recently there has been an uptick in interest in dehydrating watermelon, which produces a delicious fruit leather that can be enjoyed for up to 6 months after it has been dehydrated.

You’ll Be Growing Watermelon Every Year!

A small, round watermelon growing on a vine.

Are you feeling excited and confident about growing watermelon plants that will thrive in your own home garden? This is just the start of all there is to learn!

Want to learn more about this iconic summer fruit? Then visit our watermelon plants page to learn more about watermelon planting, growing, cooking, and more!