FruitWatermelon
Congo Watermelon
Heirloom Variety
Congo Watermelon is a giant, seeded heirloom variety that transforms summer gardens into sweet-melon paradise. These heat-loving annuals produce melons weighing up to 50 pounds with deep red flesh and sugar levels as high as 9.5%, delivering the kind of genuine watermelon flavor that makes picnics memorable. Ready to harvest in 90-99 days, Congo thrives in warm zones 3-13 and demands full sun and consistent moisture to reach its impressive size.
Photo © True Leaf Market
Growing Conditions
USDA Zone
3-13
Sunlight
Full Sun
Water
High
Soil
Well-drained, Sandy Loam, Fertile
Preferred Temp70-95°F
Growth Stats
18 in
Height
—
Width
36 in
Spacing
90–99
Days to Harvest
PeriodAnnual
TypeVine, Forb/herb
Plant Profile
Sunlight
Full Sun
Water
High
Zones
3-13
Size
18in H x ?in W
Growth
Annual
Care
High
Hover over chart points for details
Highlights
Congo melons are genuinely massive, regularly hitting 50 pounds with a sugar content that rivals the sweetest varieties available. The red flesh is classic watermelon through and through, packed with the kind of sweetness that makes kids and adults alike eager for another slice. This is an open-pollinated, organic heirloom bred for heat tolerance, meaning it actually performs better in peak summer conditions when other crops might struggle.
Common Uses
Congo Watermelon is grown primarily for fresh eating, where its exceptional sweetness and substantial size make it the centerpiece of summer meals and picnics. The large melons yield generous slices perfect for sharing, and the red flesh and high sugar content deliver that classic, refreshing watermelon experience straight from the garden.
Growing Timeline
First Bloom
Late Spring
First Harvest
Mid-summer
Last Harvest
Late Summer
Care Instructions
Direct Sow
Direct sow Congo Watermelon seeds in warm soil after all frost danger has passed and soil temperature consistently reaches 70 degrees Fahrenheit or warmer. Plant seeds 1 inch deep in full sun, spacing plants 36 inches apart with 120 inches between rows to allow room for sprawling vines.
Harvesting
Harvest Congo Watermelons 90-99 days after planting when melons reach their substantial 40-50 pound size. Test for ripeness by checking that the melon has a creamy yellow spot where it rested on soil, the skin sounds hollow when tapped, and the tendril nearest the fruit stem has dried and curled. Cut melons from the vine using a sharp knife rather than pulling, leaving several inches of stem attached to reduce stress on the plant.
Growing Calendar
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Companion Planting
Pests & Diseases
Ecology & Traits
Edible
Scientific Classification
Citrullus lanatus (Thunb.) Matsum. & Nakai
Family
Cucurbitaceae
Genus
Citrullus
Duration
Annual
Growth Habit
Vining
Native Status
L48 (I)PR (I)VI (I)
History & Origin
“Congo Watermelon is an open-pollinated heirloom variety, preserved and shared through generations of gardeners who valued both its exceptional size and superior sweetness. As a seeded heirloom cultivar, it represents the type of genetics that seed savers have maintained over decades, ensuring that gardeners today can grow the same plants their grandparents might have planted. Its development reflects a breeding focus on maximizing both flesh quality and melon weight, traits that made it a picnic staple in American gardens.”