Cocktail Grapefruit is a hybrid citrus fruit developed by the University of California Riverside that is ready for harvest during the winter. It is a cross between a sweet mandarin orange and a pummelo. This lineage gives it a large size at roughly 4 inches across and a deep rich golden-orange and thin skin. It is commonly peeled and eaten fresh out of hand like an orange but can also be halved and sectioned like a traditional grapefruit or juiced. It is thought to be heavy with seeds compared to most grapefruit but much less acidic. Cocktail grapefruit trees are dwarf cultivars and reach just 8 feet in height at maturity. They can be grown in large containers or as a dooryard or orchard tree.
Grow cocktail grapefruit in a full sun exposure where ambient temperatures typically range between 40 and 90 degrees Fahrenheit and the trees are not exposed to temperatures of 29 degrees Fahrenheit or below.
Plant your cocktail grapefruit tree in nutrient rich, well tilled, light and easy draining soil. Amend nutrient poor and heavy soils with several pounds each of compost, aged manure and coarse sand to improve fertility and drainage.
Water your tree to keep the soil evenly moist throughout the year and never allow the soil to dry out completely beyond the top inch or two of soil. Drought stress can interrupt not only foliage growth but bloom and fruiting and should be avoided at all costs.
Feed your cocktail grapefruit with a granular citrus tree fertilizer product threes times a year. Make the first application in February the second in July and the last in September. Apply according to product label dosing directions but do not exceed a total of 1 1/2 pounds of actual nitrogen per tree per year. Water in deeply after each application.
Harvest the cocktail grapefruit from the tree from December through March plucking from the branch when ripe or cutting off with secateurs. Allow the fruit to ripen fully but remove before the fruit swell or bloat from age as this will stress the tree and discourage new fruit development.