I’m not sure why you would want to grow square watermelon, but over 3 million people are interested in decorative watermelon.
Growing watermelons at home can be a rewarding and delicious endeavor for gardeners of all skill levels. Watermelons are not only a popular summertime fruit but are also packed with vitamins and minerals, making them a nutritious addition to any garden. This article will provide essential tips and guidelines to help you successfully grow watermelons in your own backyard.
Starting watermelon seedlings indoors is only recommended for cooler climates or to ensure germination. Prior to transplanting, it’s important to prepare the soil by amending it with organic matter, as watermelons thrive in loose, well-drained, and moisture-retentive soil that is rich in nutrients. Optimal planting conditions include a mildly acidic to neutral soil pH of 6.0 to 6.8, and a soil temperature of at least 65°F (18°C).
Once you have prepared the soil, it’s time to focus on proper care and maintenance. Watermelons require regular watering when first transplanted and are heavy feeders of nutrients. Paying close attention to your watermelon plants’ needs throughout their growth will result in a bountiful harvest and a satisfying gardening experience.
Choosing the Right Watermelon Variety
Seedless Watermelons
Seedless watermelons have become a popular choice for many gardeners, as they provide the convenience of enjoying watermelon without the hassle of seeds. These watermelons are scientifically named Citrullus lanatus and are developed through a special breeding process. Some popular seedless varieties include ‘Big Tasty’ and ‘Mini Piccolo.’ Keep in mind that seedless watermelons require a seeded variety nearby for pollination purposes.
Sugar Baby
The ‘Sugar Baby’ watermelon is an icebox variety, meaning it’s small enough to fit in a refrigerator easily. It is well-known for its sweet, juicy, and deep red flesh. This variety is considered an early-fruiting type, typically maturing in 70-75 days—making it suitable for cooler climates with shorter growing seasons.
Blacktail Mountain
‘Blacktail Mountain’ is another early maturing watermelon variety known for its great flavor, dark green rind, and deep red flesh. It matures within 70-80 days, which makes it a suitable choice for those with limited growing seasons. ‘Blacktail Mountain’ is an icebox variety and can be grown in small spaces.
All-America Selections
All-America Selections (AAS) is a non-profit organization that tests and promotes new plant varieties proven to perform well in gardens across North America. AAS has recognized a few watermelon varieties known for their great taste, consistent performance, and disease resistance, such as ‘Crimson Sweet,’ ‘Charleston Gray,’ and ‘Klondike Blue Ribbon.’
Recommended Varieties
Based on different factors such as growing conditions, flavor preferences, and space constraints, here are some top watermelon varieties to consider:
- Seedless: ‘Big Tasty,’ ‘Mini Piccolo’
- Icebox: ‘Sugar Baby,’ ‘Blacktail Mountain’
- AAS Winners: ‘Crimson Sweet,’ ‘Charleston Gray,’ ‘Klondike Blue Ribbon’
- Other Popular Choices: ‘Georgia Rattlesnake,’ ‘Golden Midget,’ ‘Carolina Cross #183’
Selecting the right watermelon variety for your garden will depend on your personal preferences, the space you have available, and your region’s climate. Consider these factors and explore trusted sources like seed catalogs and recommendations from local gardening clubs or extension services to find the perfect variety for your garden.
Preparing the Soil
Soil Temperature and Conditions
To successfully grow watermelons at home, it’s essential to start with the right soil temperature and conditions. Watermelons thrive in warm soil, so ensure the soil has warmed to at least 65°F (18°C) before planting. In cool climates with short growing seasons, seeds can be started indoors 2 to 3 weeks before the last frost date and transplanted outdoors when the soil is warm. To help warm the soil, black plastic can be placed over the planting area.
Soil pH and Amendments
Watermelons prefer slightly acidic to neutral soil with a pH range of 6.0 to 7.0. Before planting, measure the soil’s pH and adjust it accordingly using soil amendments like lime for acidic soil or sulfur for alkaline soil. Nutrient-rich soil is essential for watermelon growth, so consider adding well-depleted, aged manure, seaweed, or well-rotted compost to the soil. Adding organic matter can also help improve the soil’s structure and create a nutrient-rich environment for watermelons to thrive.
Drainage and Soil Structure
Proper drainage is crucial for watermelon growth as they require well-drained soil to prevent root rot or other issues. Loamy or sandy soils with good drainage are ideal for planting watermelons. Soil with a high clay content may cause drainage problems and should be amended with organic matter like compost to improve drainage or switched for a different soil type. Consider using raised rows or beds to further improve drainage and create an optimal growing environment for watermelons.
Planting Watermelons
Starting Seeds Indoors
To give watermelons a head start in regions with shorter growing seasons, start seeds indoors about 4-6 weeks before the last frost date. Sow seeds 1/4 to 1/2 inch deep in seed-starting pots in a rich, well-draining soil mix. Keep the soil consistently moist and maintain a temperature of 70°F or above for successful germination. Seedless watermelon varieties may require special care or treatments to stimulate germination.
Transplanting Seedlings
Once the young plants develop at least two true leaves, they are ready for transplanting. About a week before transplanting, begin hardening off the seedlings by gradually exposing them to outdoor conditions. Choose a sunny location in your garden with well-draining, sandy soil. If the soil needs amendment, conduct a soil test to determine necessary additions.
When transplanting, gently remove the seedlings from their pots, handling them by the leaves to minimize root damage. Place them into prepared holes in the garden, maintaining the same soil level as in their pots.
Direct Sowing Seeds
In regions with long growing seasons and warm temperatures, you can directly sow watermelon seeds. Wait until the soil temperature reaches at least 70°F and all danger of frost has passed. Sow seeds 1/2 to 1 inch deep in the garden, in soil that has been amended if necessary based on a soil test.
Spacing and Hill Formation
Watermelon plants require ample space as their vines can spread up to 10 feet or more. Space plants 3 to 5 feet apart within rows and leave at least 6 to 8 feet between rows. Hills can be formed by heaping soil to create small mounds about 12 inches in diameter. Plant 3 to 5 seeds per hill, and later thin the seedlings to the two strongest plants.
When planning your watermelon planting layout, consider using a trellis system or other supports for the vines to help conserve space and minimize the risk of diseases caused by soil contact.
Caring for Watermelons
Watering and Fertilization
Watermelons need regular watering, especially when they are first transplanted. It is essential to keep the soil consistently moist but not waterlogged. To promote healthy growth and fruiting, apply a slow-release organic fertilizer with a balanced ratio of nitrogen, phosphorus, and potassium. It is recommended to fertilize the plants during the flowering and fruiting stages.
Mulching and Weed Control
Mulching is beneficial for watermelon plants, as it helps retain moisture in the soil and suppresses weeds. A layer of straw or other organic mulch material can be spread around the base of the plants. To further help with weed control, it is also essential to practice regular hand-weeding or hoeing around the plants throughout the growing season.
Pollination and Pruning
For successful watermelon growth, adequate pollination is crucial. Watermelon plants produce male and female flowers, both of which require pollinators, such as bees or other insects, to facilitate the transfer of pollen. To encourage pollination, ensure that the plants receive full sun, as this attracts pollinators.
Pruning can improve the overall quality of the fruit and prevent overcrowding. Remove any male flowers (which do not produce fruit) when the first female flowers (with tiny watermelons at their base) appear, leaving just a few male flowers for pollination purposes.
Pest and Disease Management
Several pests and diseases can affect watermelon plants. To prevent and manage these issues, take the following precautions:
- Regularly inspect the plants for signs of pests, such as aphids or cucumber beetles, and take appropriate measures to control them.
- Practice crop rotation to disrupt the life cycles of pests and diseases.
- Remove any infected fruit, leaves, or other plant parts to prevent further spreading of diseases.
- Ensure proper spacing between plants and rows to provide adequate air circulation and prevent the spread of diseases.
By following these guidelines for caring for watermelons, you can enjoy a successful and bountiful harvest in your home garden.
Harvesting Watermelons
Signs of Ripening
One of the primary indicators that a watermelon is ready for harvest is a change in color. The fruit’s skin will transform from a bright, shiny green to a duller, more matte hue. Another sign is in the tendril nearest the fruit. The tendril will dry up and turn brown when the watermelon is ripe. Additionally, the bottom of the watermelon, where it rests on the ground, will change from a light green or white color to a creamy, yellow shade.
A simple technique to assess ripeness is the “thump test.” Gently tap on the watermelon and listen for a dull, deep sound. This indicates that the fruit is ripe and ready to harvest.
How to Harvest
To properly harvest a watermelon, follow these steps:
- Use a sharp knife or pruning shears, ensuring tools are clean to prevent disease transmission.
- Cut the stem at least an inch away from the fruit, leaving some stem attached. This helps prevent rot and extends the storage life of the watermelon.
- Handle harvested watermelons with care to avoid bruising or damaging the fruit, as this can decrease their shelf life.
Watermelons are best harvested during the cooler parts of the day, such as early morning or late evening, to ensure optimal freshness. After harvesting watermelons from your home garden, they can be stored in a cool, dark place for up to two weeks, depending on the variety and storage conditions.
Tips and Troubleshooting
Growing watermelons at home can be a rewarding experience, but it does require some attention to detail. In this section, we will cover some tips and troubleshooting ideas to help ensure a successful watermelon harvest.
One key aspect to consider when growing watermelons is the soil. Watermelons thrive in loamy, somewhat-sandy, well-drained soil with a pH between 6.0 and 7.5. It’s essential to avoid soil that contains too much clay, as it can cause drainage issues. Amending the soil with 1-2 inches of compost prior to planting can greatly improve your chances of success.
Watermelons need ample space to grow, with each plant requiring up to 20 square feet. When planting seeds, sow them 1/2″ deep in small hills or rows, spaced 36″ apart. In the hills, plant 6-8 seeds, and in the rows, plant 2-3 seeds every 36″. This will help ensure proper airflow and nutrient availability for each plant.
Hot weather is another important factor to consider when growing watermelons. They love warm temperatures and require a long growing season with plenty of sunlight. Ensure your plants receive at least 6-8 hours of direct sunlight per day for optimal growth.
When it comes to watering, keep the soil consistently moist, especially during the germination period. This may require watering at least once daily. As the seedlings grow, thin them out to the two strongest plants, providing enough space for healthy development. Regular, consistent watering is crucial, but avoid overwatering to prevent root rot or fungal issues.
If you don’t have enough space in your garden, consider growing watermelons in large mounds made of compost, worm castings, sand for drainage, and blood meal. This will help the plants meet their soil requirements and can be a solution for those with limited gardening space.
Monitoring the growth and health of your watermelons is essential for a successful harvest. Here are a few common issues and their solutions:
- Pests: Keep an eye out for pests like aphids, cucumber beetles, and spider mites. You can use organic insecticides, neem oil, or introduce beneficial insects like ladybugs to address infestations.
- Fungal diseases: Maintain proper airflow around plants and avoid overwatering to prevent fungal diseases. Treat afflicted plants with appropriate fungicides if necessary.
- Poor fruit development: Ensure proper pollination by attracting pollinators to your garden or hand-pollinating the flowers.
- Knowing when to harvest: A ripe watermelon will have a yellowish spot on the underside where it touches the ground, and the tendrils near the fruit will start to dry out. Additionally, you can listen for a hollow sound when tapping on the watermelon.
By following these tips and addressing any issues that occur during the growing process, you can successfully grow watermelons at home and enjoy their delicious, refreshing fruit.