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Duncan Grapefruit

Duncan grape fruit is one of the oldest grapefruit cultivars in America and has long been considered the gold standard for Florida grapefruit. Its luscious, pale fruit ripens early and has exceptional flavor that is sweeter than seedless grapefruit varieties. The tree grows vigorously in Tampa Bay’s warm climate, and mature trees can reach a height and spread of 20 to 30 feet. Though the fruit has seeds, it is an excellent citrus tree for Florida home landscapes. One tree can satisfy the grapefruit appetite of a family of four.

Name Citrus paradisi
Hardiness Zones 8-11
Flower Color White
Blooms Spring
Light Needs Full Sun
Water Needs Steady While Young, 40-45 inches per year
Soil Needs Moist, Well-Drained
Fruits December thru May


Duncan grapefruit trees are available in 5, 10, 15 and 30 gallon container sizes, though Keep It Green’s stock is most plentiful in the 10-gallon size. Duncan grapefruit trees can be planted out 10 to 15 feet apart in moist, well-drained soil. Plant near the south-facing side of your home to give grapefruit trees shelter from northwest winds in winter. Give Duncan plenty of water to help develop a strong root system in the first year after planting. Grapefruit trees can be fertilized just a few weeks after planting, and require less fertilizer as years go by. Duncan grapefruit trees require very little pruning to keep their shape, but check them for crossing or rubbing branches and branches that rub against developing fruit, removing them as needed.

Design Ideas

Duncan grapefruit trees bear large, pale-yellow fruit that stands out on the tree, making it an attractive addition to a sunny yard as well as a bountiful source of tasty fruit. Come in to Keep it Green, where our specialists are waiting to help you with landscape design ideas, and expert advice on soil preparation, care and maintenance of these beautiful citrus trees. While you’re here, check out our Cocktail Fruit citrus tree selections in 15 and 30 gallon sizes.

All Keep it Green citrus trees come from robust rootstock grafted by high-end growers. Each tree is state-inspected and registered for one year, according to Florida state law.