How to Grow Watermelons in a Backyard Garden

How to Grow Watermelons

Watermelons are the perfect summer fruit, loved for their juicy sweetness and refreshing taste. Growing watermelons in your backyard garden can be an incredibly rewarding experience, allowing you to enjoy fresh, home-grown produce. Because they can be picked at peak ripeness, watermelons grown at home often taste much better than those purchased at a store or roadside stand. With a little planning, care, and patience, you can grow your own watermelons in your backyard garden. Below are some tips to get started.

Choosing the Right Variety

Common watermelon varieties include Sugar Baby, Crimson Sweet, Charleston Gray, and Moon & Stars. But there are a ton of options as far as watermelon varieties go. You'll find watermelons in different shapes from round to oblong. You'll also find red, yellow, and orange-fleshed watermelons.

While they all taste great, one important consideration is fruit size. Smaller watermelons, often called "icebox", watermelons are preferred by gardeners with smaller growing spaces or those that don't want to cut a huge watermelon each time. Other gardeners with large families may prefer the larger watermelons to provide refreshment for larger groups.

Preparing the Soil for Watermelons

Watermelons will thrive in well-drained, sandy loam soil with a pH between 6.0 and 7.5. If you have clay soils or soils with poor drainage, consider adding an ample amount of compost on top of your native soil prior to planting. You can also make a hill or mound of compost for planting the watermelons. This prevents you from having to add compost to an entire plot.

Watermelons will perform best when planted in an area with full direct sun at least 6-8 hours per day. If you have access to drip irrigation (tubing or tape), we recommend using it for watermelons. Drip irrigation allows you to water only where the watermelon plants are located, conserving water and reducing weed growth between the plants.

Planting Watermelons in a Backyard Garden

How to Plant Watermelons

While they can be direct-seeded into the soil, we prefer to transplant watermelons. We plant the seeds in seedling trays 4-6 weeks before our intended in-ground planting date. Watermelon transplants should be placed in the ground once the risk of frost has passed in the spring.

Before placing your watermelon plants in the ground, sprinkle a generous amount Coop Gro organic fertilizer along the intended row of watermelon plants. Use a rake or garden hoe to lightly incorporate the organic fertilizer into the soil. Place watermelon plants approximately 2 foot apart along the row. If you're planting multiple rows, space the rows at least 4' apart, although they can be spaced wider if you have more room.

How to Water and Fertilize Watermelons

Watering and Feeding Watermelons

Watermelon plants will need consistent moisture throughout their growth cycle, especially during fruit formation. But be careful not to overwater them as the fruit is developing, as this can cause the fruit to enlarge too fast and split. Keep the soil consistently moist but not waterlogged. This is where the above mentioned part about having well-drained soil comes into play.

Drip irrigation is also a huge advantage when watering watermelons because it keeps the foliage dry. Minimizing leaf moisture on watermelons will reduce the presence of diseases like powdery mildew and downy mildew, which commonly affects watermelon plants.

Once your watermelon plants have been in the ground a couple weeks, sprinkle a a couple handfuls of Coop Gro organic fertilizer around the base of each watermelon plant. Use your hand to lightly mix it into the soil, trying not to disturb the root structure of the watermelon plants. Re-apply Coop Gro every 2-3 weeks or until you're unable to get close to the plants without disturbing them.

You don't want to step on the watermelon plants while they're growing. At some point the plants will be so dense that you won't be able to get close enough to fertilize them. But this is the big benefit of using a slow-release, organic fertilizer like Coop Gro. It will continue to feed your watermelon plants many weeks after the last fertilization.

How to Pick a Ripe Watermelon

When to Harvest Watermelons

If you ask 10 different gardeners how to tell when a watermelon is ripe, you might hear 10 different responses. Some say to thump the watermelon to see how dense it sounds. Others will tell you to look at the underside of the watermelon to see if it's pale and yellow.

The most proven way we've found is to check the tendril closest to the fruit. If you look at the watermelon vine near each individual fruit, you'll notice a small, curly tendril. As the watermelon ripens, this tendril will start to turn brown and eventually be completely dry. Wait until the tendril closest to the fruit turns completely brown before harvesting.

You can choose to eat that watermelon right then, or put it in a shaded spot where it will be good for several weeks. We've found that watermelons are at their peak sweetness when allowed to sit in the shade several days after harvesting. It's tough to wait that long sometimes, but your patience will be rewarded!

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