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How to Plant Watermelon in 8 Easy Steps

If you’re an ambitious gardener who has a passion for planting and growing different types of fruits and vegetables, you definitely have to try watermelons. Part of the reason that watermelon is a good growing option is that there are several different kinds, but they all require a similar growing and caring process. So, if your curiosity is piqued and you want to know how to plant watermelon, you’re about to find out! 

When to Plant Watermelon

How to Plant Watermelon

Before you can learn how to plant watermelon, you must first know when to plant them. Watermelon, like cantelope and many other types of melon, is warm weather fruit that requires a minimum of two or three months of warm weather to produce fruit. As such, you should plant them in early to mid-spring so that they have all summer to grow and blossom. 

If you live in tropical or southern climates where warm weather is more common, you can wait until late spring to early summer to plant watermelon. As long as they get several months of consistently warm temperatures in excess of 65 to 70 degrees, your watermelon will survive and thrive. 

What About Very Cold Climates? 

If you live in the north, where it’s going to be tough to get three consecutive months of warm weather, you’re not entirely out of luck. While it will be more difficult to grow them successfully, it can still be done. The key to how to plant watermelon in the north is to start them indoors around two or three months before the last frost of the season. 

These extra two to three weeks of indoor, climate-controlled growth is often enough to ensure your watermelon survives. 

How to Plant Watermelons 

Now that you know when to plant them let’s dig deeper into how to plant watermelon. In general, there are two different options when it comes to planting watermelon. 

How to Plant Watermelon Directly in the Ground

If you want to know how to plant watermelon like a pro, direct sowing is the preferred method. Direct sowing means that you plant watermelon seeds directly into the ground rather than starting them indoors as seedlings and transplanting them. 

The main thing to keep in mind when planting your watermelon seeds is that they need the soil to be nice and warm. Ideally, you should wait until the soil is between 70 and 90 degrees before planting. However, if you’re worried that you’ll be pressed for time, you can plant them when the soil is between 60 and 70 degrees. Remember, we’re talking about the temperature of the soil and not the ambient temperature. 

It might take the soil several days to catch up with the ambient temperature if you had a long winter. Once the soil is at the right temperature, here are the steps to follow for how to plant watermelon. 

  1. Make sure to plant your watermelon seeds in very fertile and nutritious soil. You’ll likely want to add manure, fertilizer, and other organic, natural additives to the soil before planting your seeds. 
  2. Plant the seeds around a half inch to one inch deep below the soil. 
  3. To ensure proper drainage, you’ll want to plant the seeds on small hills or rows that jut several inches above the ground. 
  4. Plant your seeds roughly three feet apart to ensure that your plant has enough room to grow and for the roots to spread. 
  5. Plan on planting two or three seeds at a time to ensure at least one of them sprouts. 
  6. Immediately after you plant your seeds, water them lightly with a can or a soft sprinkler. 
  7. When the watermelon plants are around two inches tall, you’ll want to pick the best-looking plant in the batch and cut the others down to the ground. You only want one plant in each bunch to grow because there will only be enough nutrients for one.
  8. Watermelons grow fairly fast, and you should start to see some growth within a week or two of when you initially planted them. 

How to Plant Watermelon Via Transplants

If you decide to start your watermelon indoors as seedlings and then transplant them outdoors when the weather is nice enough, here’s what you need to do if you want to know how to plant watermelon via transplantation. 

  1. First off, watermelons have very fragile roots, which means removing them from a pot and transplanting them outdoors is very difficult.
  2. Start your watermelon seeds in biodegradable, peat-free pots or seed trays. 
  3. Plant the seeds in these trays two to three weeks before the last frost of the season. 
  4. Fill your biodegradable pots with a starter mixture up to about one inch from the top. 
  5. Place three watermelon seeds into each container. 
  6. Put roughly half an inch of potting soil on top of the seeds, then give the mixture a light watering. 
  7. If you have access to a southern-facing window that gets lots of sunlight, place the containers in front of them. 
  8. If not, invest in a grow light and place the containers beneath the light, ensuring that the temperature is around 70 degrees around the seeds. 
  9. Wait until the plants are around two inches tall, and choose the best-looking plant in each pot to save. Cut the other plants down to the stem just above the soil. You only want nutrients going to the primary plant and not to any of the others. 
  10. Before planting your watermelon seedlings permanently in the ground, you’re going to want to acclimate them to the outdoors. Wait until one week after the last frost, then take each of your seedlings outside and place them in direct sunlight for roughly one hour per day for a week. Make sure temperatures are at least 70 degrees in the sunshine. 
  11. Two weeks after the last frost, you’re ready to transplant your watermelon outdoors permanently. 
  12. Start by trimming the top of your biodegradable pots or trays containing your watermelon. 
  13. Plant them in the soil of your choosing and fill them in until the soil is even with the top of the pots. 
  14. After you backfill the holes with soil, add water in increasing increments for the first week or two after planting. 

Watermelon Care

Watermelon planting

Knowing how to plant watermelon is only half the battle. You also have to know how to properly care for your plants once they start to grow. 

Light

Watermelon crave sunlight and warmth. If they don’t get enough of either one of these, they will struggle to grow to their full potential. Therefore, you want to plant your watermelon in full sunlight with minimal to no shade. The only time you want partial shade is if you’re growing melons in very hot climates such as Arizona or Florida. 

Soil

The main thing to keep in mind in regards to the soil when learning how to grow watermelons is that it needs to drain well. It should also have a pH level of between 6.0 and 6.8 and be fairly rich in nutrients. It’s wise to add fertilizer, manure, mulch, or other nutrients to the soil if you want healthy, large watermelon. When learning how to plant watermelon, soil management is second to none. 

Water

Since water is in their name, it seems fitting that watermelons need lots of moisture to grow. You should be especially heavy and consistent on the watering when you initially plant or transplant the seeds. Once you start seeing watermelon growth, you can cut back slightly on the watering. In general, you want the soil to remain moist but never flooded. 

Temperature and Humidity

Just as you want the soil temperature to be around 80 or 90 degrees when you plant watermelon seeds, you want it to remain at that temperature for most of the growing process. Humidity won’t hurt watermelon and may, in fact, help them by adding moisture to the soil. 

Fertilizer

Fertilizer is always a good option when it comes to watermelon. However, one of the most important things with knowing how to plant watermelon is knowing which fertilizer to use. It’s always best to go with organic or natural options that are rich in nutrients. If you opt for a chemically enhanced fertilizer, it’s best to choose an option that’s heavy in nitrogen initially. Once your plant starts to blossom and bloom, however, you’ll want to switch to a low-nitrogen fertilizer. 

How to Tell When a Watermelon Is Ripe

Planting Watermelon

If you’re new to the process and are just learning how to plant watermelon, it’s a little tricky to know when they’re ripe. However, here are a few telltale signs to look for to make things a little easier. 

  • The tendrils or stems at the top of the melon will start to turn brown as the melon ripens. 
  • You shouldn’t be able to cut the melon with your fingernail when it’s ripe. 
  • Melons are shiny when they’re growing initially, but they lose their shine when they ripen. 
  • The bottom of the melon where it’s been resting on the ground should be a yellow color when it’s ripe. 
  • You should never try to use the thump or tapping method to check the ripeness of your melon. While it’s a timeless method, it’s highly inaccurate, especially for beginners. 

How to Pick Watermelon

PLanting watermelon

When your watermelon are ripe and prime for picking, it’s time to reap the rewards of your hard labor. Once melons are full-grown, they typically take around two weeks to ripen. During this time, cut back on watering your plants so that the sugars inside the fruit concentrate together and add sweetness. 

The final step in learning how to grow watermelon is learning how to pick them. There’s no great trick to this process, however. You can either cut the stem of the watermelon in half, pluck it from the vine like a massive grape, or cut it at the base of the stem. In terms of everything that goes into how to plant watermelon, harvesting is the easiest part. 

Managing Pests and Disease

Downy mildew

Like all plants, vegetables, and fruits, humans aren’t the only beings that enjoy a tasty watermelon. There are plenty of diseases and pests to be on the lookout for including. 

  • Fusarium Wilt 
  • Anthracnose 
  • Gummy Stem Blight 
  • Alternaria Leaf Spot 
  • Aphids 
  • Mites 
  • Vine Borers 
  • Cucumber Beetle 

The only way you’ll be successful at learning how to plant watermelon is if you’re able to protect them from these obstacles. The best way to do this is by spraying your crop with a non-chemical repellent to drive pests away. To keep diseases from setting in, you should make sure to water your plants at their base because splashing water can trigger mold and other diseases. 

You should also make sure to buy your seeds from a reputable distributor and follow the care instructions for how to plant watermelon from your specific seeds. 

How to Plant Watermelon: Tips and Tricks

Watermelon planting
  • Regularly water your watermelon plants until they start to bloom, then cut back on watering. 
  • Once your melons are ripe and within a week of picking, stop watering them. Withholding water will cause the melon to sweeten. 
  • Make sure to give your melons plenty of room to spread out and grow, and don’t crowd them together too tightly. 
  • Give your plants an average of one to two inches of water weekly. 

Wrapping Up How to Plant Watermelon

As you can see, there’s a lot that goes into learning how to plant watermelons the right way. However, by following the steps in this article and adhering to the care instructions of your specific watermelon variety, you’ll be enjoying the juicy fruit they bear in no time! 

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!