How to grow dozens of watermelon plants in just 5 days

Growing watermelons at home might sound like a slow, complicated project but with the right germination method, you can start dozens (even hundreds!) of seedlings in under a week.

Best of all, you can do it using seeds from an ordinary store-bought watermelon! Whether you have a large garden, a backyard or just a sunny balcony, this simple guide will show you how to germinate supermarket watermelon seeds and grow strong, healthy seedlings in just five days.

Step 1: Choosing the right watermelon seeds

Start by selecting a ripe, seed-filled watermelon from your local supermarket. Seedless varieties won’t work for this method, so make sure the fruit has visible black or brown seeds inside.

Scoop out the seeds and rinse them thoroughly in clean water to remove any sticky fruit residue. After cleaning, spread the seeds on a paper towel and let them dry for 24 hours in a shaded, well-ventilated spot.

This drying step is crucial , it prevents mold and prepares the seeds for fast and healthy germination.

Step 2: Pre-Germination , the secret to speed

The key to growing dozens of watermelon plants quickly lies in pre-germination. This method jumpstarts the sprouting process before you plant the seeds in soil.

Start by soaking your cleaned seeds in warm water for 12 hours. This softens their hard outer shell, allowing moisture to penetrate and activate the embryo inside.

Next, use the paper towel germination method:

1. Moisten a paper towel so it’s damp but not dripping.
2. Spread the seeds evenly on one half of the towel, then fold it over.
3. Place the towel inside a resealable plastic bag or sandwich it between two plates.
4. Store this setup in a warm, dark place such as on top of a refrigerator or inside a cupboard.

Check daily for signs of sprouting. In warm conditions (around 25–30°C), watermelon seeds will sprout in just 3–5 days, showing tiny white roots.

 Step 3: Transplanting sprouted seeds

Once your seeds show roots about 1–2 cm long, it’s time to transplant them.

Prepare small pots or seed trays with a light, well-draining potting mix  a blend of soil, compost and sand works perfectly. Make shallow holes about 1–1.5 cm deep, and carefully place each seed root-side down. Cover lightly with soil and water gently.

Keep the soil moist but not soggy. Place your trays in a bright, warm spot that receives at least 6 hours of indirect sunlight daily.

Within days, the seedlings will emerge and start growing strong green shoots.

Step 4: Caring for young seedlings

Once your watermelon seedlings develop their first true leaves, they’ll need a bit more care and attention. Here’s how to keep them thriving:

• Provide ample light: Watermelon seedlings love the sun. If natural light is limited, use a small grow light to keep them strong and compact.
• Maintain consistent moisture: Water gently whenever the top layer of soil feels dry.
• Thin out crowded seedlings: Remove the weaker ones so the strong plants have enough space to grow.

After about a week of indoor growth, your watermelon seedlings will be sturdy enough for outdoor life.

Step 5: Hardening off and outdoor transplanting

Before moving your seedlings outdoors, they need to adapt gradually, a process known as hardening off.

For 5–7 days, place your seedlings outside for a few hours each day, slowly increasing their exposure to sunlight and wind. This helps strengthen their stems and leaves.

Once nighttime temperatures stay above 18°C (65°F) and there’s no risk of frost, you can transplant them into your garden or large pots.

Outdoor growing tips for maximum harvest

To ensure your watermelon plants grow strong and produce sweet, juicy fruits, follow these outdoor care tips:

• Spacing: Keep at least 1 meter (3 feet) between plants to allow vines to spread.
• Soil: Choose a sunny, fertile and well-drained spot enriched with compost or manure.
• Watering: Keep the soil evenly moist, especially during flowering and fruiting stages. Avoid overhead watering to prevent disease.
• Mulching: Apply straw, dry grass or sugarcane mulch around the base to retain moisture and control weeds.

Depending on the variety and your climate, expect to harvest your watermelons in 70–90 days from seed planting.

In just five days, you can transform supermarket watermelon seeds into dozens of healthy seedling, ready to grow into juicy, refreshing fruits.

This easy method is not only fun and affordable but it’s also a sustainable way to experience the joy of growing your own food from something you might have thrown away.

Simple. Sustainable. Satisfying.Give it a try,your future harvest of homegrown watermelons awaits!

Author: Moureen Koech

Moureen Koech is a passionate Digital Journalist, an adept Agribusiness Writer with a keen eye for news and an impactful story-teller,whose stories provide key value to Agripreneurs and stakeholders in the Agricultural sector