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Welcome to the world of watermelon cultivation in the great state of Oklahoma! If you’re a gardening enthusiast eager to grow these juicy and refreshing fruits in your backyard, you’ve come to the right place. Oklahoma’s climate offers a unique set of challenges and opportunities for watermelon growers, and knowing when to plant is crucial for a successful harvest.

In this article, we will explore the optimal timing for planting watermelon in Oklahoma, taking into account the state’s climate, soil conditions, and other factors that can affect the growth and development of this beloved summer fruit. So, grab your gardening gloves and let’s dive into the world of watermelon cultivation in the Sooner State!

Best varieties of watermelon to grow in Oklahoma

In Oklahoma, the climate is generally hot and dry, so it’s important to choose watermelon varieties that are well-suited to these conditions. Here are a few watermelon varieties that tend to grow well in Oklahoma:

  1. Crimson Sweet: This is a popular variety known for its sweet, juicy flesh and dark green skin with light green stripes. It has good disease resistance and can tolerate the heat well.
  2. Sugar Baby: This is a smaller watermelon variety that matures quickly, making it suitable for shorter growing seasons. It has a sweet, crisp flesh and a dark green rind. Sugar Baby is also known for its good disease resistance.
  3. Black Diamond: This variety produces large, oblong watermelons with a dark green rind and sweet, juicy flesh. It is known for its excellent flavor and can tolerate the heat well.
  4. Charleston Gray: This variety is known for its large, oval-shaped watermelons with a light green rind and sweet, red flesh. It has good disease resistance and can handle the hot Oklahoma summers.
  5. Jubilee: This variety produces large, round watermelons with a light green rind and sweet, red flesh. It has good disease resistance and can handle the heat well.

Remember to provide your watermelon plants with plenty of sun, well-drained soil, and regular watering to ensure optimal growth and fruit production.

When to plant watermelon in Oklahoma

The best time to plant watermelon in Oklahoma is typically in late spring or early summer, once the soil has warmed up and the risk of frost has passed. This is usually around mid to late May. Watermelons require warm soil temperatures of at least 70°F (21°C) for optimal germination and growth. Planting too early when the soil is still cool can result in poor germination and slow growth. It is also important to ensure that the average daily temperature is consistently above 70°F (21°C) for successful watermelon growth.

How to grow

Growing watermelon requires careful planning and attention to detail. Here are the steps and considerations to keep in mind:

  1. Climate and Location: Watermelons thrive in warm climates with a long growing season. Choose a location that receives full sun for at least 6-8 hours a day. Ensure the soil is well-draining and rich in organic matter.
  2. Soil Preparation: Prepare the soil by removing weeds, rocks, and debris. Watermelons prefer slightly acidic soil with a pH level between 6.0 and 6.8. Amend the soil with compost or well-rotted manure to improve fertility and drainage.
  3. Planting: Start watermelon seeds indoors 2-3 weeks before the last frost date in your area. Transplant seedlings outdoors when the soil temperature reaches at least 70°F (21°C). Alternatively, you can sow seeds directly into the ground once the soil has warmed up. Space the plants 3-4 feet apart in rows that are 6-8 feet apart.
  4. Watering: Watermelons require consistent moisture, especially during the fruiting stage. Water deeply, providing around 1-2 inches of water per week. Avoid overhead watering to prevent diseases. Mulching around the plants can help retain moisture and suppress weeds.
  5. Fertilization: Watermelons are heavy feeders. Prior to planting, incorporate a balanced organic fertilizer into the soil. Once the plants start to vine, side-dress them with nitrogen-rich fertilizer every 3-4 weeks. Be cautious not to over-fertilize, as it can lead to excessive foliage growth and fewer fruits.
  6. Pollination: Watermelons require pollination for fruit set. Bees and other pollinators are essential for this process. Encourage pollinators by planting flowers nearby or using bee-friendly practices in your garden.
  7. Pruning and Training: Watermelon vines can become sprawling, so consider providing support or trellising to keep them off the ground. Prune off any excessive foliage or lateral vines to redirect energy towards fruit production.
  8. Pest and Disease Management: Common pests include aphids, cucumber beetles, and squash bugs. Monitor your plants regularly and use organic pest control methods if necessary. Watermelons are susceptible to diseases like powdery mildew and fusarium wilt. Rotate crops, provide good air circulation, and avoid overhead watering to minimize disease risks.
  9. Harvesting: Harvest watermelons when they are fully ripe. Look for signs like a dull skin color, a yellowish underside, and a hollow sound when tapped. Cut the fruit from the vine, leaving a few inches of stem attached.

By following these steps and considering the specific needs of watermelon plants, you can successfully grow delicious and juicy watermelons in your garden.

When to harvest

Watermelon should be harvested in Oklahoma when they are fully ripe, which typically occurs in late summer or early fall. The exact timing can vary depending on the specific variety of watermelon you are growing and the weather conditions in your area. However, as a general guideline, you can start checking for ripeness around 80-90 days after planting the watermelon seeds. Look for the following signs to determine if the watermelon is ready to be harvested:

  1. Color: The skin of a ripe watermelon will have a deep, uniform color. For example, a dark green watermelon will turn a duller shade of green or yellowish when ripe. Additionally, the underside of the watermelon (where it touches the ground) should have a creamy yellow color.
  2. Sound: Give the watermelon a tap with your knuckles. If it produces a deep, hollow sound, it is likely ripe. If the sound is dull or flat, the watermelon may still need more time to ripen.
  3. Texture: Gently press the skin of the watermelon. Ripe watermelons will have a firm but slightly yielding texture. If the skin feels too hard or too soft, it may not be fully ripe.
  4. Tendril drying: Check the tendril closest to the watermelon’s stem. If it has turned brown and dried up, it is a good indication that the watermelon is ripe.

Remember to also consider the average days to maturity for the specific watermelon variety you are growing, as this can help you estimate the harvest time more accurately.

Common watermelon plant problems and fixes

Common problems when growing watermelon include:

  1. Poor pollination: Watermelon plants require proper pollination for fruit development. If there is a lack of bees or other pollinators in your area, you can hand-pollinate the flowers using a small brush or cotton swab. Gently transfer pollen from the male flowers to the female flowers.
  2. Blossom end rot: This is a condition where the bottom of the fruit develops a dark, sunken area. It is caused by calcium deficiency or inconsistent watering. To prevent blossom end rot, ensure the soil is rich in calcium by adding lime or gypsum before planting. Maintain consistent soil moisture by watering deeply and regularly.
  3. Powdery mildew: Powdery mildew is a fungal disease that appears as a white, powdery coating on the leaves. To prevent powdery mildew, provide adequate spacing between plants for good air circulation. Water the plants at the base to avoid wetting the foliage. If powdery mildew appears, treat it with a fungicide specifically formulated for powdery mildew.
  4. Pest infestations: Common pests that attack watermelon plants include aphids, cucumber beetles, and squash bugs. Monitor your plants regularly and take action at the first sign of infestation. Use insecticidal soap, neem oil, or other organic insecticides to control pests. You can also use physical barriers like row covers to protect young plants from pests.
  5. Over or under-watering: Watermelon plants require consistent moisture, especially during fruit development. Over-watering can lead to root rot, while under-watering can cause poor fruit development. Water deeply and regularly, ensuring the soil is evenly moist but not waterlogged. Mulching around the plants can help retain soil moisture.
  6. Improper fertilization: Watermelon plants need a balanced fertilizer with a higher ratio of nitrogen in the early stages and a higher ratio of phosphorus and potassium during fruiting. Use a slow-release organic fertilizer or apply a liquid fertilizer according to the package instructions. Avoid excessive nitrogen as it can result in lush foliage but fewer fruits.

By addressing these common problems and following proper care practices, you can increase your chances of successfully growing watermelons.