Warm-Season Vegetable

When to Plant Watermelon in Rhode Island

The ultimate summer treat. Watermelons need heat, space, and patience — but the payoff is pure joy.

The Short Answer

In Rhode Island, watermelon planting dates vary by region. Since watermelon are frost-sensitive, start seeds indoors 3 weeks before your last frost, then transplant outside 2 weeks after frost danger has passed. Rocky, acidic New England soils. Sandy near coast. Glacial deposits throughout. Amendment needed for most vegetable...

Rhode Island Frost Dates

Your planting dates depend on which part of Rhode Island you're in. Here are the frost date ranges by region:

Region	Zones	Last Frost (Spring)	First Frost (Fall)
Rhode Island	6a, 6b, 7a	Apr 15 - May 5	Oct 5 - Oct 25

Watermelon Planting Schedule for Rhode Island

Rhode Island (Zones 6a, 6b, 7a)

Average last frost: Apr 15 - May 5 · Average first frost: Oct 5 - Oct 25

Start Seeds Indoors

3 wks before frost

Transplant Outside

2 wks after frost

Direct Sow

3 wks after frost

Growing Watermelon in Rhode Island

Watermelon in Rhode Island's Climate

Watermelon is achievable with transplants and short-to-medium season varieties. Start indoors 3 weeks before last frost. Black plastic mulch warms soil for earlier transplanting. Crimson Sweet (80 days) is the most popular variety. Your warm July-August provides the sustained heat watermelons need for sweetness.

Soil Considerations for Rhode Island

Rocky, acidic New England soils. Sandy near coast. Glacial deposits throughout. Amendment needed for most vegetable gardening. Make sure soil has warmed to at least 70°F before planting watermelon outside.

Rhode Island Climate & Growing Season

Maritime climate moderates temperatures. Four seasons. Moderate growing season. Ocean influence reduces frost risk near coast. Watermelon cannot tolerate any frost, so wait until all frost danger has passed before transplanting outside. Watch local forecasts carefully in spring.

Growing Tips

Black plastic mulch warms soil faster. Check ripeness by looking for a yellow ground spot and listening for a hollow thump.

Companion Planting

Plant watermelon alongside these companions for better growth:

Corn Sunflowers Marigolds

Keep watermelon away from:

Potatoes

The Bottom Line

Watermelon can be grown successfully across Rhode Island, but your exact planting dates depend on which region you're in. Rhode Island gardeners should plan around a Apr 15 - May 5 last frost, while those in Rhode Island can typically plant later. For exact dates based on your zip code, use our free planting date finder.

Note: All dates are based on NOAA 30-year Climate Normals and represent historical averages, not predictions for any specific year. Always check your local weather forecast before planting frost-sensitive crops. Learn about our data sources.

Last reviewed: March 29, 2026