Do certain foods remind you of certain people? For me, it’s watermelon. The time of year rolls around to begin planting and harvesting my crops, and I instantly think of my mother-in-law.
It was her favorite time of year. Some of my fondest memories of her include shucking corn on my back porch, and her constant craving for watermelon all summer long.
Considering how many watermelons she ate throughout our many hot summers gardening together, I’ve become somewhat good at growing them.
With this in mind, I wanted to share the process of how to grow watermelons successfully. It’s my hope many other families can enjoy hot summers together, shucking corn and eating watermelon.
Here’s what you need to know to grow delicious and satisfying watermelon:
Quick Gardening Info for Watermelons:
- Hardiness Zones: 3, 4, 5, 6, 7, 8, 9, 10, 11
- Soil: Loamy, PH between 6.0 to 7.0, well-drained, rich in organic matter, work the soil with compost or well-rotted manure before planting
- Sun Exposure: Full sun, at least 6 hours of sunlight per day
- Start Indoors: 3 to 4 weeks before the last frost date
- Start Indoors (in fall): 112 to 151 days before the first frost date
- Hardening Off: 7 to 10 days before transplanting
- Transplant Outdoors: 2 weeks after the last frost date
- Spacing: 3 to 4 feet between plants and 5 to 6 feet between rows
- Depth: ½ to 1 inch seed depth, transplant slightly deeper
- Best Companions: Radish, corn, nasturtium, pumpkin, squash, citrus
- Worst Companions: Potato
- Watering: Give 1 to 2 inches of water per week while the plants are growing, blooming, and setting fruit
- Fertilizing: Apply high nitrogen fertilizer, fish emulsion or liquid manure 3 weeks after planting, and again after flowering
- Common Problems: Thrips, cutworms, flea beetles, cabbage looper, aphids, aster yellows, angular leaf spot, verticillium wilt, anthracnose, alternaria leaf blight, alternaria leaf spot, cercospora leaf spot, downy mildew, fusarium wilt, gummy stem blight, powdery mildew, bacterial fruit blotch, blossom-end rot, mosaic
- Harvest: Harvest when the the tendrils closest to the fruit are beginning to dry out and turn brown
Best Watermelon Varieties
There are different categories of watermelon. It’s important to understand the varieties which fit into each category. This way you’ll know which option to choose per occasion.
1. Picnic Watermelons
These watermelons are the perfect size to take on a picnic where you’ll have plenty of people gathering. They usually range anywhere from 16 pounds to 45 pounds and take 80 or more days to reach full maturity.
A few varieties of picnic watermelons are:
- Charleston gray
- Black diamond
- Crimson sweet
2. Orange Watermelons
The name gives this category away. You’ll know you’ve found a watermelon which fits into the ‘orange’ category by its orange toned flesh.
These varieties can have seeds or no seeds. Whichever best suits your preference. The types of orange watermelons are:
- Desert king
- Yellow baby
- Yellow doll
3. Seedless Watermelons
Seedless watermelons are a great option if you’re someone who hates spitting out those pesky seeds. Just know that seedless watermelons do have tiny seeds, which are more difficult to notice.
These watermelons usually weigh between 10 and 20 pounds and take 80 or more days to mature. Varieties of seedless watermelon are:
- Queen of Hearts
- King of Hearts
- Jack of Hearts
4. Fridge Watermelons
This type of watermelon is usually referred to as an ‘icebox watermelon’ because you can keep them in the icebox and is enough for one to two people. Watermelons from this category usually only reach five to fifteen pounds.
The most common variety of this type of watermelon is the sugar baby. It’s petite and a great option if you want a taste of watermelon but aren’t planning on feeding a crowd. This variety will fit easily in your fridge as well.
How to Plant Watermelon
You should plant watermelons when the soil has reached at least 70 degrees Fahrenheit. If you live where you have a shorter growing season, it would be a good idea to start your seeds indoors. However, directly sowing them is recommended as it will give you the best watermelon harvest.
Starting Watermelon Indoors
If you live where the climate remains colder for more extended periods of time, you’ll have to start your seeds indoors. Here’s what you need to do:
1. Cover the Ground with Plastic
To begin, you’ll need to cover the area you’re planning on planting your watermelons with black plastic a month before planting. This will attract sunlight and warm the soil.
2. Move Indoors
Next, you’ll need to begin prepping your seeds no more than three weeks before transplanting. The reason being, smaller transplants do better than larger.
You should place three seeds per larger cell pack. Sow each seed a half inch deep in the cell pack.
3. Care for Your Seeds Until Transplant
When your seeds are sown, you’ll need to place them on a heat mat, under grow lights, and near a south facing the window. The goal is to keep the seeds at 80 degrees Fahrenheit.
From there, you’ll care for them like you do all seedlings. Be sure to water them as needed.
However, the trick is to pay attention to which seedlings are doing the best. You’ll need to thin out your cells to where only one is remaining for transplant per cell pack.
4. Plant in Mounds
When it’s time to plant, place the transplants in mounds as you would if you were planting seeds. I’ll go into greater detail of how to properly plant watermelon seeds a little later in this article.
Growing Watermelons as Lawn Cover
If you have a large lawn, you may be looking for ways to get away from mowing it all the time. Watermelons could be your solution. Here’s what you need to know:
1. The 40/40 Rule
Keep in mind; watermelon vines can reach out to 20 feet from their growing location. You want ground cover, but you don’t want to overdo it.
2. Mix and Plant
Next, you’ll mix the manure and potting soil. You’ll plant eight seeds in the mound you’ve created with the soil and manure.
When the seeds begin to sprout, you’ll thin the mound down to only three seedlings. They should be the best of all of the seedlings which popped up.
As the vines grow, you’ll have to mow around them, but they should slow the growth of the grass beneath them which equates to less mowing in the area where the watermelons grow.
3. The Finished Product
Finally, you’ll finish the year out by picking your delicious watermelon. When they’re done producing, you’ll cut up the vines and clean up the area.
From there, you should spread out the soil and manure and water deeply. In a few weeks, you’ll have lush and green grass where the watermelons once grew.
Planting Watermelons in Your Garden
Planting watermelons in your garden is a little different than growing them on your lawn. To grow watermelons in your garden, you’ll need a good-sized space.
As I’ve already mentioned, watermelon vines can reach up to 20 feet from their original growing location.
You’ll need to create mounds of dirt, referred to as hills. Be sure to amend your soil as needed with compost and other organic matter to give your watermelons the best possible grow space.
Keep in mind; watermelons prefer soil with a pH of 6-6.8 if you’d like to test your soil for adequate conditions.
Inside the hills, you should plant eight to ten watermelon seeds. Plant each seed one inch deep in the hill. Be sure to place each hill four feet apart and keep a distance of eight feet between rows.
Once you’ve planted your seeds, it’s a good idea to fertilize. Use a fertilizer which is high in nitrogen for the best results.
As the seeds begin to pop up, you’ll need to thin the plants down by picking the best three seedlings in each hill.
Caring for Your Watermelon Plants
Watermelons are low maintenance plants. They require very little care and produce better flavor the less care you provide. Here are the few things you need to do to care for your watermelons properly:
Add a thin layer of mulch around the hills of watermelon seeds and under where the vines will run. It will help to keep grass and weeds to a minimum.
Also, consider mulching with a sheet of black plastic. This will kill any grass or weeds which try to grow up, keep the soil warm, and also keep your fruit clean.
You should fertilize watermelon plants three times during their growing season. Once when planting, the second time when the vines are beginning to run, and the third time is when the fruit is forming.
3. Withhold Water
Finally, you shouldn’t need to water your watermelons at all unless you’re in the midst of a drought. As the fruit begins to mature, withhold water because it helps the fruit to become sweeter.
4. Add Straw or Cardboard
As your fruit begins to ripen, it’s a good idea to place straw or cardboard beneath it. This will put a layer of protection between your fruit and the moisture from the ground.
It should also help deter any rot from taking place and spoiling your harvest.
Common Problems with Watermelon
Watermelons don’t have many issues, but you need to be aware of the few pests and diseases which can destroy your crop. Here is what you should look out for:
Aphids are in practically every garden. They cause your plants to become deformed and misshapen. Getting rid of them requires only a few simple solutions:
- Spray with cold water
- Spray with soap, cold water
- Add beneficial insects to your garden
- Companion planting (such as planting catnip to deter aphids.)
2. Fusarium Wilt
Fusarium wilt is a fungal disease which causes your plants to wilt and die. With most funguses, the best way to beat them is to apply a fungicide to the plant.
3. Cucumber Beetles
Cucumber beetles are another common problem in most gardens. You’ll know you have them by your plants wilting, having holes in them, and stems being munched on.
The easiest way to deter these pests is to apply an insecticide and add row covers.
However, keep in mind, watermelons need to be pollinated. Be sure to remove the row covers when the plants begin to bloom.
4. Vine Borers
Vine borers are another common insect to watch out for. If you notice your plants are suddenly beginning to wilt, but you don’t see any above-ground pests, this usually means the pest is below the ground.
In this case, the larvae of eggs which were laid in the ground before the growing season, have come alive and are eating your vines from within.
Again, you’ll need to apply an insecticide and row covers to rid your garden of these pests.
Best and Worst Companion Plants for Watermelons
Watermelons have certain plants which help them to grow better and some which hinder their growth. Here are the best companion plants for watermelons:
Potatoes and pole beans are excellent sources of added nitrogen to the soil, which watermelons love. The worst companion plants for watermelons are:
- Black walnut trees
Black walnut trees produce a toxin in their nuts which is poisonous to watermelons. Cucumbers, squash, and zucchinis all attract the cucumber beetle. This is one of the biggest pests to watermelons.
Harvesting and Storing Watermelon
Harvesting and storing a watermelon is simple. You’ll know watermelon is ripe by its underbelly. When you pick up a melon and check where it’s been lying on the ground, if the melon is white – it’s not ripe.
However, if the melon is off-white or yellow, you’ll know the melon is ripe and ready to pick.
When you want to harvest a watermelon, cut the stem close to the fruit. You can store the watermelon uncut for ten days. However, if you cut a watermelon, you’ll need to wrap it tightly in plastic and store it in the fridge for four days.
Well, you now know how to grow, care for, harvest, and store a watermelon. Now I want to hear from you. Do you have any tricks for growing a large, sweet watermelon? We’d love to hear it!
Leave us your comments in the space provided below.