How To Grow Watermelon: The Ultimate Guide To Summer’s Bounty

Ed Wike
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Watermelon: Quick Care Guide

A watermelon does quite well with moderate watering. Don’t let the fruit dry out, but don’t overwater either. When the soil is moist, set it down for 15 minutes near a drainage hole so some moisture drains into the hole.

Feed your watermelon every three to four weeks with liquid fertilizer or with a water-soluble fertilizer.

If your baby watermelons get wrinkly, attractively brown, or appear deflated, it is a sign that they are not getting enough water. On the other hand, if they are very puffy, wrinkled, and crisp, it is a sign that they have been getting too much water.

If you are wondering which watermelon is the best for you, you first need to understand your climate. Watermelons are not all bred for summertime use. They come in different shapes and sizes, with different skin tones, and ripening times. How do you know what will thrive in your area, and what will require more water than you can give? Start by choosing the right watermelon varieties for your climate.

Determinate Watermelons

Determinate watermelons are bred to be harvested all at once. They are very compact, with a bush-like growth pattern. In fact, when you are looking at the melon, the stem is slightly below where the watermelon begins to curve in. Most of the watermelons that are easier to grow are determinate, including the Crimson Sweet and Royal Ann.

Intermediate Watermelons

An Intermediate type melon will mature over a longer period of time. They will form a rounded shape, rather than a spherical shape. They are not extremely large, but they take longer to mature. An Intermediate type watermelon is ideal for the mid-continental United States and areas where the growing season is longer than Florida, but shorter than Alaska.

A Note About Seedless Melons

Seedless watermelons are not a new thing. The first seedless watermelon grown in the world was developed in the middle of the 20th century. Recent sales of seedless watermelons have increased dramatically in the last years. There are some benefits of using them.

For one seedless watermelons are very easy to pick. No worries about being punctured by seeds that could have been left over from a picker. Prior to the hulling process, watermelons are usually manually cultivated to ensure no bad seeds remain but you can’t trust 100% a machine to catch every single bad one.

Another great thing about growing seedless watermelons is that they don’t have to go through the process of developing vines from a cotyledon. Since vines and cotyledons develop from different types of genetics, the process is much faster without them. It is also much easier to control the watermelons through the growing process. Since there is no need for periodic cotyledon checks, the watermelons can be grown organically. This is very good news for people that are trying to eliminate any type of harmful chemical exposure in their lives.

Common Watermelons

  • The name “watermelon” comes from the flesh’s high water ratio, which makes this fruit a great source of hydration.
  • There are two basic types of watermelon: seedless and seeded. Seedless watermelon is obviously better choice if you don’t want to waste time cutting them out.
  • White flesh watermelons are not as sweet as the red ones, but easier to digest and better for people suffering with diabetes.
  • A yellowish-green melon is most likely a decoy, it’s filled with seeds instead of flesh.
  • An oblong watermelon is not allowed for commercial sale, its shape makes it less appealing.
  • A traditional watermelon features three colors: red, yellow and green.
  • A miniature watermelon grows to around 2-3 pounds, compact in size and makes an excellent accessory for the dinner table.
  • A seedless baby watermelon is developed for small growing areas.
  • The giant watermelon is a favorite among watermelon growers. It’s very juicy, containing up to 20% sugar content.

Icebox Watermelons

Ice box watermelons are not bred to be icy and chilled. An ice box water-melon, just like a regular watermelon, is best when eaten ripe. However, icebox watermelons are known to store better than regular watermelons. That’s because regular watermelons tend to lose their crispness and become semi-soft after a few days. Icebox watermelons are genetically engineered to stand up to the rigors of shipping and still taste perfectly ripe after a few days.

People who live near the equator don’t have to worry about icebox watermelons. These fruits originated in Asia and India and only grow in areas where the temperature is high enough for regular watermelon farming.

Differently-Colored Watermelons

All watermelons start out green. As they ripen, they turn different shades of red. Watermelons grown without chemical pigments can vary in color from yellow to almost black when ripe.

Watermelons contain lycopene, a chemical believed to assist with weight control, healthy skin, fighting cancer, and maintaining vision. Watermelons are loaded with vitamins A and C as well as potassium. They also have calcium, but you won’t get much of it because the biggest part of the watermelon rind is made of water.

How To Grow Watermelon From Seed

Watermelons are usually started indoors. You know that this is the case if you notice that the seed packets have no germination date. Most people start them indoors in their house or in a greenhouse.

Watermelons also require a fairly long growing season, between 90 and 120 days.

Seeds that are planted indoors will typically take about two weeks to germinate.

Once the seeds have sprouted, it is best to plant them in a container first. Make sure you brighten the lights and that the room is between 65-75 degrees Fahrenheit.

While they are in this stage, watermelons shouldn’t be fertilized.

Be prepared that you may have to transfer your watermelon plant to a larger pot.

It is usually when they start making their first set of leaves that you will need to start fertilizing them.

When To Plant Watermelon

When you grow watermelon, there are a variety growing zones. Knowing the planting time for your area, along with some simple care instructions, will increase your chances of harvesting big watermelons.

Most seed companies that sell watermelon seeds recommend direct sowing versus transplanting. If you live in an area where the winters are mild, you might consider direct sowing the seed. You simply sow the seed into the ground in mid-summer.

In cooler areas with frost, you should transplant the seedlings indoors. If you know many days are required before the last frost of the season, start the seeds indoors at least three weeks before you expect to set them outdoors. You can place the seedlings in the ground when there is at least 10 to 14 days that the temperature will be above 55 degrees.

As watermelons grow, you should space the plants at least 25 to 36 inches apart to allow enough room for the plants to mature and develop. You can set the plants on mounds of soil to allow for ventilation and drainage. The soil should be slightly acidic and allow for plenty of water and nutrients to reach the roots.

Where To Plant Watermelon

Watermelons are warm-weather plants, and so will thrive best in a warm climate. If you live in a cold area, you can keep your watermelons inside for the winter months, but they will rarely grow there. They will never sprout in temperatures below 50 degrees, and will do poorly in temperatures above 88 degrees.

If you live in a warm climate, you will want to plant your watermelons in the heat of the summer months. Watermelons should be planted when the temperature is between 75 and 95 degrees. Planting watermelons too early or too late can result in rotting.

When you plant watermelons in the summer, it is easy to see what temperatures the soil is getting and how it is doing. Check the soil before planting to make sure it is the correct temperature. To check, take your hand and scoop out the soil. If the air temperature is around 75 degrees, then the soil will be about the same temperature. Avoid shrubs and trees that may shade your melons.

How To Plant Watermelon

Watermelon is a member of the sweet cucumber family, and they require similar growing conditions. The plants that you choose to grow should be a crossbreed of the Ben Davis and the Charleston Grey melons. These two varieties are the sweetest and the easiest to eat. Most watermelons that you will buy are these variations of these two varieties.

As soon as the last expected frost has passed, and the soil temperatures stay warm at night, that is when you know it is time to plant them. You can actually plant them by seed in late spring, but the seeds are hard to find. What you need to do is start your watermelon plants indoors about 3 weeks before the last frost, and grow them until they are about a foot tall. The best sunlight for watermelon plants is a sunny location, with part shade. After the Melons get about 5 to 6 feet tall, they will need staking to keep them up.

When choosing your watermelon plants, you will want to look for watermelons that are green and hard. If they are turning light green, then they are getting ready to ripen, which doesn’t happen until they are actually picked. Yellow green melons are easy to grow, and they grow very quickly. Black variety melons are harder to grow, and they take a lot longer to get ripe.

Caring For Watermelon Vines

Watermelons prefer a sunny climate and need warm soil to grow in. It also helps to keep the area well-watered. Irrigation can be done through drip irrigation. The most common vines are the Charleston grey, the seedless, and the Texas specialty varieties.

The first three varieties need vining varieties. The Texas special does not need the vining variety but still needs to be tapped down because they tend to grow very fast.

Each vine needs about eight feet of room when fully grown. The vines are usually fast growing and the pumpkin-shaped melons that develop are about the size of a coconut.

Something else you may need is a trellis. The plants can grow up to six feet per day or more during the summer. Push the melons all the way to the top as they mature. The vines can grow vines. It is recommended that you buy the plants with vined vines.

The melons will soar upwards and should be pushed up a trellis as they grow, on both sides.

Make sure you train them up a strong trellis as they can grow very fast.

The watering needs to be at least twice a week as watermelons like to drink a lot of water. Also, they like to drink more when the temperatures are hot.

Sun

It’s not rocket science: a watermelon won’t grow well if it lacks sun. And sun is what gives it its dark green color and the ability to grow a lot of produce.

So, the first step towards growing watermelon at home is to place your watermelon seedling in a sunny area.

Keep in mind that there are a couple of considerations in place that will affect the amount of sun it gets, directly or indirectly. These considerations involve the length of day, surrounding buildings, fences and trees.

If the day is very long with only a few clouds in the sky, the watermelon plant will need extra protection. Extra fruit on the vine could leave your watermelon fruit vulnerable to sun damage, which will trigger a number of problems later. So, if that’s the case, be sure to put up a net to protect it.

The other thing to keep in mind is that watermelons are a nighttime-exerting plant. They require a certain level of darkness and quiet at night, and interruptions will cause the plant to stop growing.

Temperature and Humidity

Your climate and growing conditions will largely dictate when to get started with your plants and when to harvest your fruit. In areas with cold winters, your watermelons won’t be ready to harvest until the next summer. The closer they are grown to the equator, the more quickly they will reach maturity, so there is an advantage in doing some research and finding out how much longer your summer season is going to be.

When it comes to growing your own watermelons in shorter seasons, you have a few options to help you speed things along. If there is a greenhouse or another indoor location that you can use, you can keep your watermelons ready for harvest year-round. Otherwise, you can start with your seeds inside and then move them outside after the ground temperature is consistently warm during the day. Giving them as much sunlight as you can, and keeping them well watered and consistently warm, will prepare your plants for when it is time to harvest. When you choose your location, there are a few things to keep in mind. The ground should be well-drained and in full sun. The soil should be loose but well-compacted to keep your plants healthy. Make sure that the location is free of any items that might harm your plants, like chemicals and fertilizers, and that the area is protected from animals.

Watering

Watermelons are fairly tolerant to a range of soil moisture levels. However, too much or too little can both cause the watermelon to drop its blossoms and prevent fruit from developing. To encourage development and make sure the fruit develops, keep the following in mind.

Check soil moisture levels once a day.

Water melons need about 1 to 1.5 inches of water each week, and it is best to water them one or a few inches at a time. You can determine how much you need to water, in part, by the conditions: dry and hot weather will increase water needs. When you water, use the later watering method, as the earlier ones can encourage disease and can cause fruit split.

How To: Prep and Maintain Your Shovel

Snow shoveling is hard on shovels, especially if the snow is heavy or wet.

Your shovel needs to be ready to work when you need it, and this requires the proper storage and preparation.

Proper storage is storing your shovel in a location where it will be out of the elements and can stay dry.

If you make the hanger yourself from scrap lumber, make sure that you use wood screws that are rust resistant. Rusting can destroy the blade of your shovel, so making sure it is protected against rust is essential.

Soil

Watermelons need 10 to 12 hours of full sun each day. They do not tolerate wet soil, so be sure to prepare the area where you will plant to have good drainage. You also need to have bone dry soil after the danger of frost has passed. Construct raised beds if you have very heavy soil, otherwise adding organic matter will help friable, light soil drain faster.

Once you have prepared the soil, water the bed before planting. The watering should be a thorough drenching of the soil, not a few sprinkles. Be sure to let the soil dry to the touch before planting the seeds. An optional step you can take is to pre-irrigate the bed. If you do pre-irrigate, be sure to plant the seeds in the best location for the water to drain.

The plants need good drainage to be sure that the plant’s roots do not rot, so be sure the way you water is good drainage. Drip irrigation is excellent, but a hose with a watering wand also works well. Make sure the water is evenly dispersed on all of the plants. If you do not like getting your hands muddy, then use a watering can. You can find watering cans with long handles which are easier to use on higher plants. Make sure to water all of the plants, even those that are not in danger of wilting. You should water once a day.

Fertilizing

Like other fruits and vegetables, watermelons need an appropriate level of nutrients for healthy growth and development. Fertility is the soil needs to provide sufficient nutrients for the watermelon to fruit. The fertilizing process is not difficult, but you need to be careful not to over or under fertilize as it can be very detrimental for the watermelon vine. In several soil types, the potential fertility is high, so fertilizing is not necessary. In addition, if your soil is free of the major limiting factors, the garden is organic, the soil is loamy, and it has compost available, you can forego fertilizer completely and concentrate on other aspects such as crowding, pest control, and harvesting time. However, in low fertility soil, fertilizing is critical.

Propagation

Soil-less medium: Watermelon plants are propagated by seeds. However, this season you may try to grow watermelons using the 11" Jiffy pellets. It makes the situation somewhat easier.

The seeds have to be sown in a container. Now is the time to decide, whether you want to start growing in a container or directly in the ground. You can grow watermelons in a container that can be placed in an indoor pot.

For indoor sowing, use an empty seed container with drainage holes. Fill it with a soilless seed starting mix or vermiculite. Sow the seeds into the soil mix so that they do not touch each other, their surface gets covered with the mix. However, don't bury them deeply. Water the seeds with distilled water.

Watermelons thrive in light. However, you should keep the container covered with two layers of translucent plastic. The layer should not touch the soil. The growing medium of the watermelon plant should be kept moist. Never allow the seeds to dry out.

Transplanting: Watermelons are heat-loving, so they can grow in a greenhouse; otherwise, they can be grown in a greenhouse with a seed tray. Sow the seeds 2'' (5cm) apart. Plant it at soil line. Now fill the tray with equal parts of peat moss, perlite, vermiculite, and sand.

Transplanting

Watermelons should be transplanted once the ground is warm. Early spring or late summer planting for watermelon plants is recommended since winter conditions are not viable where the plants will be growing.

The best time to transplant watermelons is once the weather is starting to warm up. Be sure to provide your watermelon with plenty of water while it is being relocated. Also, you want to make sure that the soil at its new location remains well watered.

Once you have settled your watermelon plant into its new home, keep it well watered. After transplanting, watermelons need an abundance of water. Overwatering causes many problems, so avoid this practice.

The size of the hole the watermelon plant is transplanted into will dictate how much room it has to grow. Watermelons require a lot of room to grow, so make sure that your hole is large and at least a few feet deep.

After the hole for the watermelon has been dug, you need to make sure your new transplant is situated correctly to ensure that it will be able to receive all the water it needs for proper growth.

Dig a hole that is twice the width and the same depth as the root ball that has been cut from the watermelon plant.

Overfill the hole with water and allow the excess water to drain.

Use your shovel to level the hole and then put your watermelon into the hole.

Pruning

Watermelons grow on vines that can grow up to 60 feet long. They require a lot of space and must be trained and harvested. They should be planted in sandy soil that drains easily and receives full sunlight.

Pruning for a single vine should begin three weeks after planting and continue every few weeks throughout the growing season. Watermelons should be pruned selectively so that the plant receives about six hours of sun exposure every day and is also receiving about 20 inches of water per week.

To prune watermelons correctly, remove suckers and watermelons that are growing in the wrong places. You can do this by either cutting the side that has the next largest watermelon attached to it off the vine or by cutting the side vine completely from the vine itself. Watermelons should not be pruned until at least three weeks have passed, so you need to inspect your watermelon vines twice per week.

Determining how far your watermelons are growing from the ground is crucial to how you prune. If the watermelon is growing too low, it is probably because it has not been pruned in a while and there's a lot of new growth. If the watermelon is growing too high, you may need to prune off the top of the vine to direct more nutrients to your watermelons.

The Importance Of Mulching

Mulching is the best thing you can do to ensure the fastest production and the best quality of your watermelon crop. This is an essential part of the process that can’t be skipped. Mulching makes sure that there is adequate moisture around the growing fruit or even the newly germinated seeds.

Also, mulch will suppress weeds, which means you won’t have to do much weeding, which otherwise will keep you away from your crop since you have to keep the watermelons moist. This is very important since watermelons need to stay moist 24/7 during the growth process.

Simply having watermelons growing on your property can make you look like a professional farmer. It is as if you are taking care of a real, profitable business. To really be professional about it, you will do whatever it takes, implement the best strategies and use the appropriate tools for the job.

This is one of the ways you can get an advantage over the majority of the population. Not many people are willing to take their watermelon business all the way. But if you want to get the very best harvest, then you will take that extra step to ensure your harvest will be the best it can be.

Training Watermelon Vines

Watermelon is a vine that does not grow on trellises or wires. The vines grow on the ground and you need to provide support for the fruit by building a fence and placing a cage around the watermelon.

For a single plant you can use a basic four-foot by four-foot cage.

For multiple plants: You need to install support wires a foot off the ground. Section the cage into one section per plant, taking care to keep about 8 to 10 inches between the plants. If you space the cages tight, the vines will just run into one another and not grow properly.

Watermelons tolerate a light frost, but if you are expecting temperatures below 28 degrees Fahrenheit, you should place a blanket over the vines to protect them.

Once the fruit starts to grow, the plant is very susceptible to adverse weather, so be sure to cover it if it looks like rain, or if the weather is colder than usual. The fruit should be completely covered at night.

Harvesting And Storing Watermelon

Watermelons are ready to harvest when the underside of the one-inch thick fruit begins to change from green to pale yellow. The flesh will also have tiny black seeds that also turn black when ready for harvest. Use the tip of a small, sharp knife to cut out long strips around the watermelon, starting at the bottom of the fruit, at one end, and continuing around to the other end. Put pressure on the knife so that you cut more than penetrate, to prevent the watermelon from being damaged.

To harvest the water melon ball first cut the watermelon in halves, using the long top of the fruit as one half, and the bottom as the other. Place the halves on a flat surface, and using either a sharp knife or an electric cheese cutter, cut the watermelon into balls. Sort the melon balls into two colours; round and long. The round shape are better for eating while the long melon spears and chunks are better for cooking. Store the watermelon in an airtight container (buckets, bins, or plastic tubs with tight fitting lids are ideal), storing by colour for ease of use. This will preserve the sweetness of the watermelon for up to two weeks.

Harvesting Watermelons

An Orlando Sentinel headline in June 2002 proclaimed, “How sweet it was!” The story inside focused on the nostalgia felt by Central Floridians for watermelons. In the days of yesteryear, the newspaper says, “It was the sweetest, juiciest, reddest, freshest-tasting watermelon to be found. The only problem was the only place where it was sold was the watermelon patch.”

Then a chain of supermarkets created a demand for fancy melons. They encouraged producers to change the shape and color of their fruit and introduced small personal melons. The once-loved fruit immediately lost popularity.

To remedy the situation, the Sweet Betsy Honey, Company, located in Vernonia, Oregon, offers a line of watermelons called HoneyBells. These yellow orbs are sold with seeds and rind.

The watermelons got their start in China about 5,000 years ago. Chinese legend has it that watermelons were discovered when a rabbit bit into a cantaloupe-like fruit, causing its insides to spill out. Watermelons were brought to the Americas in the 16th century by explorers, and the fruit soon became commonplace from coast to coast.

Storing Watermelons

As the saying goes, nature abhors a vacuum. When you’re stealing a baby from its mother’s womb, you’re taking something that was supposed to be there. It requires intense action to remove the baby from its rightful place, and nature counters with an intense effort to bring things back into balance. When you steal something away, you’re pushing things into a state of imbalance. So the more you take, the more you have to exert your labor to keep things stable.

Abundance

If you create an abundance of something, you can reasonably remove some of it without the disruption caused by stealing.

For example, when you grow a garden, you have a lot of vegetables. If you take some of them, it doesn’t disrupt the balance of the garden. You take, but you also produce.

The more that you produce, the more that you can take without the risk of upsetting the natural order.

Now, take that principle and apply it to your life. Once you’ve set yourself up to produce, you can allow your labor to generate some of the outcomes that you want. With minimal inputs, and at the peak of your productivity, you can produce valuable outcomes without depleting your resources or your health.

Preserving Watermelon

Watermelon is a favorite summer snack for many people and an essential summer crop for those living in warmer climates. The juicy, sweet fruit is easy to grow with minimal effort, making it a great choice for hobby farmers and school children alike. But if you are growing a watermelon for the first time or don’t have a green thumb, you will want to know how to grow watermelon.

Harvesting Watermelons

Watermelons can be harvested well into autumn in warmer climates. The exact time you harvest a watermelon depends on your region and your growing conditions. Start inspecting your watermelon for ripeness when it’s about the size of a softball. The underside of the green is the best indicator, which should turn a creamy yellow color.

With a sharp knife, cut away the melon from the vine and slice it in half. Using a spoon, remove the seeds and cut the melon into pieces that you can eat. Cover and refrigerate any leftover melons for up to 2 weeks.

Freezing Watermelon

Watermelon can be frozen if thawed in the refrigerator the day before eating it. Slice the fruit into pieces and store in freezer bags. Watermelon can also be cooked whole and frozen for a hearty dessert.

Troubleshooting Watermelon Problems

Have you ever tried growing watermelon and failed? Most watermelon plants end up dying, even if you follow our guide. What's happening?

Most people either overwater watermelon plants or don't water them enough. Both things will kill your watermelon crop. Are you overwatering your watermelon? Below is a chart that we use to properly water our watermelons. Follow this chart and your watermelon should grow perfect.

Here’s an easy way to remember the amount of water to give your watermelon plant on each watering. The recommended watering amounts are the same for flooding and for deep watering.

Container Watering Watermelon Water Needs

5 Gallon Pot 6.1 to 7.8 gallons

10 Gallon Pot 12.1 to 14.3 gallons

20 Gallon Pot 23.4 to 30.4 gallons

Spread the water around the entire base of the plant and water well. If you're using a drip system, water at the base and slowly move up the plant so you don't miss any of it. Repeat this on the first and third watering of each week or every other day.

If there's no rain, give your container plants their first watering on Wednesdays. If there's a good rain, it's okay to hold off until the following Wednesday.

Growing Problems

It might sound silly, but you may have a problem with your watermelon if it grows wrinkled and hard on the outside, with irregular indentations on the rind. This is usually caused by a nutrient deficiency, for which the solution is to amend the soil with more of the primary nutrient.

Have a look at the plant. If you see webbing or small flying insects living in the soil, you may have a problem with a mite. As a solution, you can encase the stem and the ground around it with a fine mesh screen.

A bacterial blight is also possible, which manifests itself in spots that not only damage the plant, but also the fruit. This is caused by a bacterium, for which the solution is to spray a copper-only fungicide.

Another solution to try, if you come across any of those problems, is a good watering. Or, if that doesn’t help, just grow your watermelon in a different type of soil.

If you get a parasite or a deficiency, you might see your watermelon drooping. If that happens, you can simply cut the flower from the plant, which will force the plant to divert its energy to the fruit that needs it most.

Pests

Growing watermelons is hard enough without having to worry about crooks stealing them, but the truth is that a good sized watermelon can net you a decent amount of cash if it should happen to go missing. While this is not a reason to grow less watermelons (you had better think of a few other reasons if you want to give up on your dreams of watermelon bounty), it is a good time to consider some ways you can protect your watermelons from being stolen.

Pests are another issue that you can deal with in a number of ways. Birds, particularly crows and seagulls, love watermelon, and if there is one thing that can put a damper on your watermelon harvest, it is the realization that a bunch of birds have eaten most of them instead of your family. There are a few ways to prevent this from being a problem. First, you can put netting over your watermelon plants to keep the birds from getting to them. You can also add CDs to the stem of the watermelon for the final four weeks of the growing cycle. The CDs will make a distinctive noise when the watermelons are touched by the birds. You can also try sprinkling table salt on the CD. Just make sure it is not iodized salt. Iodine can prove toxic to plants when it is used for this purpose. Salt tends to work better in this specific case.

Diseases

Affecting Watermelon Plants:

Anthracnose

This disease is characterized by leaf spots that turn brown and die. Watermelons with anthracnose might show some white mold on the affected areas. Irrigation methods applied on the plant may also promote the development of the disease.

Bacterial Diseases

These diseases are characterized by soft water-soaked spots that appear on the plants. The spots may turn a creamy white if the infection has already spread in the plant.

Fungal Diseases

This type of watermelon disease is characterized by a soft rot to the lesions of the stems, petioles, and leaves. Stem cankers are common among plants that have been infected with the disease. In some cases, spots covered with rust-colored spongy mycelium might form. The fungus-caused diseases are usually caused by Fusarium oxysporum, Diaporthe cubensis, Phomopsis sp., and Macrophomina phaseolina. These diseases are also known as wilt diseases because they cause the plants’ stems to weaken and collapse.

Dehydration of the Fruit…

Even if your watermelon plant is healthy, inadequate watering can still lead to dehydration.