How Long To Grow Watermelons

How long to grow watermelons depends on the variety, but most watermelons take between 70 and 100 days from planting to harvest.
 
If you’ve been asking yourself how long to grow watermelons, the short answer is that it varies based on whether you’re growing them from seed or transplants, the climate you live in, and the specific type of watermelon you choose.
 
Some smaller varieties can be ready in as little as 65 days, while larger heirloom types might take up to 120 days.
 
In this post, we’ll break down how long to grow watermelons, what factors affect that timeline, and how to know exactly when your melons are ripe and ready to pick.
 
Let’s dive in.
 

How Long to Grow Watermelons: The Typical Timeline

When figuring out how long to grow watermelons, you’ll want to think in terms of days to maturity, which is the number of days from transplanting or germination to harvest.
 
Here’s a general breakdown:

1. Days to Maturity by Variety

How long to grow watermelons really comes down to the variety you pick.
 
Small icebox types like Sugar Baby usually take 70 to 75 days.
 
Medium varieties like Crimson Sweet need about 80 to 85 days.
 
Large heirlooms like Charleston Gray can take 85 to 95 days or more.
 
So if you’re planning your garden, always check the seed packet for the specific days to maturity.
 

2. Starting from Seed vs. Transplants

If you start watermelons from seed directly in the ground, add about 7 to 10 days to the total.
 
That’s because germination takes time, and the seedlings need to establish before they start growing vigorously.
 
Transplants skip that early stage, so how long to grow watermelons from transplants is usually closer to the listed days to maturity.
 
This is why many gardeners start seeds indoors 3 to 4 weeks before the last frost.
 

3. Climate and Growing Conditions

Watermelons love heat, and how long to grow watermelons depends heavily on temperature.
 
In warm southern climates with long summers, they grow fast and may mature a week or two earlier than expected.
 
In cooler northern areas, the same variety might take an extra 10 to 14 days.
 
Soil temperature also matters, since cold soil slows germination and early growth.
 

Factors That Affect How Long to Grow Watermelons

Several things can speed up or slow down how long to grow watermelons, and knowing them helps you plan better.
 

1. Sunlight

Watermelons need at least 8 to 10 hours of direct sunlight daily.
 
Less sun means slower growth and a longer wait.
 

2. Watering

Consistent moisture, especially during flowering and fruit set, keeps vines healthy and productive.
 
But overwatering can cause root problems that delay how long to grow watermelons.
 

3. Soil Nutrients

Rich, well-drained soil with plenty of compost gives watermelons the fuel they need.
 
Too much nitrogen, though, leads to lots of leaves and fewer fruits.
 

4. Pollination

Bees are essential because poor pollination means misshapen or slow-growing melons.
 
If you notice few bees, you can hand-pollinate to keep things on track.
 

How to Know When Your Watermelons Are Ready

Knowing how long to grow watermelons is one thing, but knowing when to pick them is just as important.
 
Here are the signs to look for:

1. The Tendril Test

Check the curly tendril closest to the fruit.
 
When it turns brown and dries up, the melon is ripe.
 

2. The Thump Test

Give the melon a firm tap.
 
A ripe watermelon sounds deep and hollow, not dull or solid.
 

3. The Field Spot

Look at the underside where the melon rested on the ground.
 
A creamy yellow spot means it’s ready, while white or green means it needs more time.
 

4. Skin Texture

The skin should feel slightly rough and dull, not shiny.
 
A shiny rind usually means the watermelon isn’t fully ripe yet.
 

So, How Long to Grow Watermelons?

How long to grow watermelons ranges from about 70 to 100 days for most varieties, though smaller types can be ready in 65 days and larger heirlooms may take 120 days.
 
How long to grow watermelons depends on whether you start from seed or transplants, your climate, sunlight, water, and pollination.
 
By choosing the right variety for your region and watching for signs like the dried tendril, hollow thump, and creamy field spot, you’ll know exactly when to harvest.
 
So plant with confidence, give them plenty of sun and care, and enjoy the sweet reward when harvest time arrives.