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When watermelon starts to grow, it kicks off one of the most exciting stages in your garden.
Those tiny green fuzzballs suddenly appear, and you know all your hard work is about to pay off.
But once your watermelon starts to grow, the real work begins if you want sweet, juicy fruit instead of a bland disappointment.
So let’s talk about exactly what to do when your watermelon starts to grow, step by step.
In this post, you’ll learn how to care for watermelon once it starts to grow, from watering and feeding to protecting the fruit until harvest day.
What to Do When Watermelon Starts to Grow
When watermelon starts to grow, your job shifts from plant care to fruit care.
The vine has done its part by setting fruit, and now you need to give that little melon the best possible conditions to swell, sweeten, and ripen.
Here’s what matters most.
1. Keep the Soil Consistently Moist
Watermelon is roughly 92 percent water, so when the fruit starts to grow, consistent moisture becomes critical.
Aim for about an inch of water per week, delivered deeply at the base of the plant.
Avoid overhead watering because wet leaves invite mildew and fungal disease.
And don’t let the soil dry out completely between waterings, since irregular moisture can cause blossom-end rot or cracked fruit.
2. Feed the Vine, Not the Fruit
Once watermelon starts to grow, switch to a fertilizer lower in nitrogen and higher in potassium and phosphorus.
Too much nitrogen at this stage gives you massive vines and tiny, tasteless melons.
A dose of potassium-rich fertilizer every two to three weeks helps the fruit develop sugars and deepen its color.
Stop feeding about three weeks before you expect to harvest, since late feeding can delay ripening.
3. Thin Out Competing Fruits
This one hurts a little, but it’s necessary.
If your vine has set more than two or three watermelons, pinch off the smaller ones so the plant can pour its energy into fewer fruits.
When watermelon starts to grow in abundance, the vine spreads itself too thin and every melon ends up mediocre.
Fewer fruits mean bigger, sweeter watermelon at harvest time.
Caring for Watermelon as It Grows
Your watermelon needs protection and attention as it develops, and a few smart habits make a huge difference.
1. Put Straw or Cardboard Under the Fruit
As the watermelon grows, it sits directly on the soil, where moisture and pests can rot the underside.
Slip a piece of cardboard, a wooden board, or a bed of straw underneath each fruit.
This simple trick keeps the melon dry, discourages bugs, and prevents soft spots from forming.
2. Shield It From Pests and Animals
When watermelon starts to grow, word gets around fast in the animal kingdom.
Birds, squirrels, raccoons, and even your own dog may show interest in the sweet fruit.
Drape bird netting over the patch or set up a low fence to keep critters out.
Check the underside of the fruit regularly for signs of insect damage or tiny holes.
3. Watch for Disease and Rot
Growing watermelon is vulnerable to powdery mildew, anthracnose, and fruit rot.
Remove any yellowing or spotted leaves immediately so disease doesn’t spread to the fruit.
Keep the area around the vine free of weeds and debris, since good airflow is your best defense.
When to Harvest Watermelon That’s Been Growing
Knowing when to pick your watermelon is the final and most important skill.
A watermelon that’s been growing for about 80 to 100 days is usually ready, depending on the variety.
Check the tendril closest to the fruit, and when it turns brown and dry, that’s your cue.
The spot where the melon rested on the ground should shift from white to creamy yellow.
And the skin should feel tough, with a dull thud when you knock on it.
If your watermelon starts to grow and you follow these steps, you’ll be rewarded with fruit that’s sweet, heavy, and ready to slice.
So, What Should You Do When Watermelon Starts to Grow?
When watermelon starts to grow, your focus should shift to steady watering, smart feeding, and protecting the fruit until it ripens.
Keep the soil moist, thin out extra fruits, cushion each melon off the ground, and watch closely for pests and disease.
With a little patience and attention, the watermelon growing in your garden will reward you with a harvest worth waiting for.