When To Plant Watermelon In Nc

If you’re planning to grow watermelon in North Carolina, timing is everything. Knowing exactly when to plant watermelon in NC is the first step to a succesful harvest.

Our climate varies from the mountains to the coast, so getting your seeds or transplants in the ground at the right moment makes all the difference. A late frost can wipe out young plants, while planting too late cuts into your growing season. Let’s break down the optimal schedule for your garden.

For most of North Carolina, the safe window for planting watermelon outdoors is from late April through mid-June. The key factor is soil temperature, not just the last frost date.

Watermelons need warm soil to germinate and thrive. You should wait until the soil is consistently at least 70°F. A good rule of thumb is to plant 2 weeks after the average last spring frost date for your specific area.

NC Planting Dates by Region

Because North Carolina has three distinct growing regions, your timing will vary.

Coastal Plain (Eastern NC): This region warms up first. You can typically plant from mid-April to early June. The long, hot summer is ideal for watermelons.
Piedmont (Central NC): Aim for late April or early May through mid-June. Be mindful of late frosts in the spring.
Mountains (Western NC): The season here is shorter and cooler. Wait until mid-to-late May and finish planting by early June. Choosing faster-maturing varieties is crucial here.

Starting Seeds Indoors vs. Direct Sowing

You have two main options for getting your plants started. Each has it’s benefits.

Starting Seeds Indoors

This method gives you a head start, especially in the Piedmont and Mountains. Begin seeds indoors about 3-4 weeks before your expected outdoor planting date.

Use biodegradable pots to avoid disturbing roots later.
Plant seeds ½ inch deep in a seed-starting mix.
Keep them warm (80-90°F) until germination, then in a sunny window.
Transplant outdoors after hardening off and when soil is warm.

Direct Sowing in the Garden

This is the simplest method and works well in the warm Coastal Plain. Sow seeds directly into your garden bed once the soil has reached 70°F.

Plant seeds 1 inch deep in small mounds or hills.
Space seeds about 2 feet apart, with rows 5-6 feet apart.
Thin seedlings to the strongest 2-3 plants per hill once they have a few leaves.

Choosing the Right Watermelon Variety for NC

Selecting a variety suited to our climate and your season length is a major factor for success. Look for disease resistance as well.

For Longer Seasons (Coastal, Piedmont): You can grow larger, longer-season melons like ‘Carolina Cross’ (potential giant), ‘Crimson Sweet’, or ‘Black Diamond’.
For Shorter Seasons (Mountains, late plantings): Choose early-maturing varieties (70-85 days) like ‘Sugar Baby’, ‘Golden Midget’, or ‘Yellow Doll’.
Disease-Resistant Picks: Varieties like ‘Fascination’ or ‘Revolution’ offer resistance to common issues like fusarium wilt.

Preparing Your Garden Bed

Watermelons are heavy feeders and need lots of space and sun. Proper bed prep sets them up for strong growth.

Sunlight: Choose a spot that gets full sun—at least 8 hours of direct light daily.
Soil: They prefer sandy loam soil that drains well. Amend heavy clay soil with compost.
pH & Fertility: Aim for a soil pH between 6.0 and 6.8. Mix in several inches of aged compost or a balanced fertilizer before planting.
Space: Ensure you have enough room. Vines can sprawl 10-20 feet. Using a trellis for smaller varieties can save space.

Caring for Your Watermelon Plants

Consistent care through the summer is what leads to sweet, juicy fruit.

Watering

Water deeply and regularly, especially during fruit set and growth. Aim for 1-2 inches per week. Use drip irrigation or soaker hoses to keep leaves dry and prevent disease. Reduce watering as fruit mature to concentrate sugars.

Fertilizing

Feed plants with a balanced fertilizer when vines begin to run. When flowers appear, switch to a lower-nitrogen, higher-phosphorus/potassium fertilizer to encourage fruiting. To much nitrogen will give you lots of leaves but few melons.

Weeding and Mulching

Keep the area around young plants weed-free. Once vines spread, they will shade out weeds. Applying a layer of black plastic or straw mulch warms the soil, retains moisture, and keeps fruit clean.

Pollination

Watermelons need pollinators. You’ll see male and female flowers (female have a tiny fruit at the base). Avoid using pesticides that harm bees. If pollinator activity is low, you can hand-pollinate by transferring pollen from male to female flowers with a small brush.

Common Pests and Problems in NC

Stay vigilant for these typical issues.

Cucumber Beetles: These spread bacterial wilt. Use row covers early in the season or apply appropriate organic controls.
Aphids: Blast them off with water or use insecticidal soap.
Powdery Mildew: A fungal disease that looks like white powder on leaves. Choose resistant varieties and ensure good air circulation.
Blossom End Rot: Caused by calcium uptake issues due to irregular watering. Maintain consistent soil moisture.

How to Tell When Your Watermelon is Ripe

Harvest time is the best part. Here’s how to know when your melon is ready.

The Curly Tendril: Look at the curly tendril on the stem near the fruit. When it turns brown and dries up, the melon is likely ripe.
The Spot: The underside (where it rests on the ground) should change from white to a creamy yellow.
The Sound: Thump it. A ripe melon will have a deep, hollow sound. An unripe one sounds tight and metallic.
Days to Maturity: Check the seed packet’s “days to maturity” as a general guide from the time fruit sets.

FAQ: Planting Watermelon in North Carolina

What is the latest you can plant watermelon in NC?

For a fall harvest in the Coastal Plain and Piedmont, you can plant as late as early July if you choose a short-season variety (70-80 days). In the Mountains, aim to have fruit maturing by early October, so late June is usually the cutoff.

Can I plant watermelon seeds from a store-bought melon?

You can, but it’s not recommended. Many commercial melons are hybrids, so seeds may not produce fruit true to the parent. They also might not be adapted to NC diseases. It’s better to buy seeds from a reliable supplier.

How long does it take to grow a watermelon?

Most watermelon varieties need 80-100 days from planting to harvest. Smaller, icebox types can mature in as little as 70 days. The count starts from seed germination or transplanting, not from when the fruit appears.

Why are my watermelon plants flowering but not producing fruit?

This is often a pollination issue. Lack of bees, rainy weather, or high heat can affect pollination. You might also be seeing only male flowers early on; female flowers will follow. Be patient and consider hand-pollinating.

Getting your planting timing right is the foundation for a great watermelon crop in North Carolina. By following these regional schedules and care tips, you’ll be well on your way to enjoying your own homegrown, sweet summer fruit. Remember to keep a garden journal each year to note what worked best in your specific location.