Growing your own garden from seed opens up hundreds of different options when it comes to what you can grow. Watermelons are one of those garden plants that are different from your normal garden selection of peppers, tomatoes, and cucumbers and are so fun to grow yourself!

Growing conditions and needs vary greatly from plant to plant, so to help you be as successful as you can be, here are some tips for planting and growing the best watermelon patch this summer!

Make Sure They Have Plenty of Space

Watermelon plants grow big and can easily take over a large space. When planting, be sure to give them plenty of space and plant them between three and five feet apart in mounds. Plant 6-10 seeds in each mound, and as they begin to sprout, thin the plants and keep the three strongest looking seedlings.

Is it Warm Enough?

Make sure the soil is warm enough for planting as well! Watermelon plants prefer the soil to be 70 degrees or warmer, which usually happens near the end of spring/beginning of summer. To be safe, wait at least two to three weeks past the average last frost date (generally around the first week of May or after Mother's Day). You can place black plastic over the area where you intend to plant, and this will help warm up the soil.

Fertilize!

Before you even start to plant your watermelon seeds, amend the soil with compost or some other rich organic matter such as chicken or sheep manure. This will push nutrients into the soil that will help give your plants a strong start. As your watermelon plants continue to grow, you will need to fertilize more. Watermelons have huge appetites since they are producing such large fruit, so fertilizing is key! For best results, use a nitrogen-rich, continuous-release fertilizer from the time you plant until you notice the first flowers beginning to open. Once flowering begins, switch to a fertilizer that is higher in phosphorus and potassium such as African violet food or liquid seaweed. Switching the fertilizers like this will help provide your watermelon plants with the specific nutrients they need throughout the different phases of growth.

Give Your Plants Lots of Water

Just like they need lots of food, your plants will also need lots of water! Installing a drip irrigation system is highly recommended as overhead watering greatly increases the risk of your plant contracting a fungal disease such as powdery mildew. Watering from below the foliage of the plant keeps the water off the leaves, lessening the risk of disease, and also makes sure that the water comes into direct contact with the soil, increasing the amount of water that is readily available to your plants. Consistent watering is key, as your plants will be most sensitive to drought from the time the seeds were planted to when the vines start to produce fruit. The soil should be kept moist, but not soggy or waterlogged, for best results. In the heat of the sun, it is typical for the leaves of the plants to wilt. They do this not necessarily because they are underwatered, but to conserve energy. The leaves of your plants should perk right back up in the evening once the day begins to cool. If they do not return to normal by the next morning, consider increasing the amount you are watering.

Protect the Fruit from Critters

Ripening watermelons that sit directly on the soil can be at a high risk of molding or getting munched on by all the little critters that crawl through the soil of your garden. Laying down a layer of straw or mulch before your plants get large will not only help the soil around the plants retain water and reduce the number of weeds in the area, but it will also keep your fruit out of direct contact with the soil, thereby decreasing the risk of rot. If you don’t put down straw or mulch in time, you can also always place the fruit on a flattened cardboard box once the fruit grows to the size of a softball.

If you have other larger critters getting into your watermelon patch, covering them with a laundry basket with a couple rocks or bricks stacked on top is an easy way to keep unwanted rodents away from your ripening fruit.

Does Pruning Your Watermelon Plants Help Promote Bigger Fruit?

This is a highly debated subject. It used to be thought that pruning or trimming back extra vines that do not have fruit attached would help direct the energy of the plant towards greater fruit development. Doing so, however, only hinders the plant's production. The leaves of your plant are what help produce the sugars needed to produce ripe, sweet fruit. So, trimming back leaves and extra vines will only lessen the number of sugars produced to help encourage the ripening of the fruit.

You can prune off melons that are not developing as well as other melons. If any fruit is irregular or rotting, removing this fruit from the plant will help push more energy to the rest of the plant and will help grow the other fruit bigger, healthier, and tastier. It is also a good practice to remove any blossoms that develop within fifty days of the first average frost date (generally around the first week of October). These blossoms will not have time to produce anything substantial before the weather turns cold, and pinching them off will make sure that all energy is being focused on the current fruit and making sure they ripen before the first frost.

Know When to Harvest

Watermelons take a long time to mature, so be patient! They require a long growing season of at least 80 days, and all of your fruit will typically ripen within two weeks of each other. You will know your melons are ripe and ready to be harvested when they turn from a bright green to a dull green color. The part of your melon that is in contact with the ground will also change from a greenish-white color to a rich yellow color when the melon is ripe. Another way to check for ripeness is to knock on your watermelon. If they are ripe, knocking on them will produce a deep, hollow sound. Familiarize yourself with the sounds of your melons as they grow. Tapping on smaller melons that have not reached maturity will produce a sound that is more high-pitched and tinny sounding. Being familiar with how an unripe fruit sounds will help you be able to better discern the sound of ripe melon.

If you can tell your watermelons are getting close, reduce how much you water for a week before you harvest. This will cause sugars in the plant to concentrate in the fruit, giving you tasty and delicious melons. Watering too much in the final stage of growth can reduce the sweetness of the fruit.

Enjoy!

After you harvest your watermelons, they will keep just fine on your counter for two to three weeks. Storing the melons in a cool area will help increase their longevity. If you cannot eat them all in time, chop them up and freeze the fruit for future use in delicious smoothies, refreshing popsicles or lovely summer cocktails! You can also always share the bounty with friends, family, and neighbors!

Questions?

If you have any questions about how to grow watermelon, please let us know! We are always happy to help answer any questions you may have. We also have helpful garden planners available in our online store that outline planting, growing, and harvesting requirements for hundreds of different garden fruits and vegetables in a compact and easy-to-read format. Here at Bath Garden Center & Nursery, it is our mission to help you grow better naturally. Happy gardening!

Sources:

"Growing Watermelons." Bonnie Plants. Web. Date Accessed: 20 July 2021. https://bonnieplants.com/how-to-grow/growing-watermelons/