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Grapefruit

Citrus (SI-trus par-ih-DEE-see)

Family: Rutaceae Unknown Understory (15-40 ft)

One of the newest citrus fruits, grapefruit is a small evergreen tree in the Rutaceae family that grows 10 to 30 feet tall and just as wide and usually has sharp thorns on its twigs. Grapefruit are grown in tropical, sub-tropical climates around the world. In the 19th century, it was found growing in Barbados, and in most of Jamaica. Originally, it was thought that grapefruit was a mutation of the pumelo. In the mid 1900s, citrus specialists decided it was an artificial hybrid cross between an orange and a pumelo. The fruit is pale yellow (when ripe) with areas of pink and has several varieties with pale yellow, nearly white, pink, or even deep red pulp. The fruit is very juicy, and the juice is acidic. In cooler zones it can be grown in a container that can be overwintered indoors. Grapefruit requires full sun and cannot tolerate shade. It prefers a deep, well-drained but moist, loamy soil. Do not overwater. Established plants are drought tolerant. It prefers a pH of 5 - 6 and is sensitive to high salinity. Grapefruit will tolerate a neutral or alkaline pH range as well with proper fertilization. They need very little pruning, only to keep its shape or to remove dead or damaged branches. Grapefruit are propagated by grafting as seeds will not produce fruit true to type. The leaves, flowers and the fruit are all used for medicinal purposes. Grapefruit are high in Vitamin C which is good for the body. A concentrate prepared from the flowers can be taken to overcome insomnia. The fruit and its juice can improve an appetite and aid in digestion. Also, as a cardiotonic. The pulp is considered an effective aid in the treatment of urinary disorders. Leaf extractions have shown antibiotic activity. Plant outside in full sun for year-round enjoyment in tropical or subtropical climates or put in a planter for movement inside when the weather turns cold. If you choose to leave some of the fruit on the tree throughout the winter, it will continue to ripen on the tree and become sweeter. Be aware that in doing so, it may reduce the size of the following year's harvest. Insects, Diseases, and Other Plant Problems: This plant can cause contact dermatitis in some people. Many of the same insects and diseases affecting the sweet orange also affect the grapefruit. The tree is highly susceptible to citrus canker and several viruses including crinkly leaf virus, psorosis, tristeza, xyloporosis, and infectious variegation. The Clemson Cooperative Extension Home and Garden Information Center has a factsheet on common citrus insect and related pests.

Source: NC State Extension Gardener Plant Toolbox ↗ NC State Extension Gardener Plant Toolbox, 67 attributes.

How it fits the guild

Guild layer 2 - Understory (15-40 ft) Optimal soil pH Acid (<6.0); Alkaline (>8.0); Neutral (6.0-8.0)
See companions & conflicts ↓

Companions & Conflicts

Curated pairwise relationships between this plant and others in the library — who feeds whom, who competes, who confuses the pests. Green reads as a good pairing, red as one to avoid.

No curated interactions recorded for this species yet.

Also noted by NC State

Related species the NC State Plant Toolbox flags for this plant — look-alikes to tell apart, and plants that play a similar role in a planting. Ones we carry in the library are linked.

Fills a similar niche Citrus x aurantiifolia Citrus x limon Citrus x sinensis

Full plant profile

Growing Conditions
Plant type
Edible; Houseplant; Tree
Life cycle
Woody
USDA zones
9a, 9b, 10a, 10b, 11a, 11b
Light
Full sun (6 or more hours of direct sunlight a day)
Soil texture
Loam (Silt); Sand
Soil pH
Acid (<6.0); Alkaline (>8.0); Neutral (6.0-8.0)
Soil drainage
Good Drainage | Moist
Available space
24-60 feet
Mature size
Height: 15 ft. 0 in. - 30 ft. 0 in. | Width: 15 ft. 0 in. - 30 ft. 0 in.
Growth rate
Medium
Maintenance
Low
Canopy layer
2 - Understory (15-40 ft)
Form & Appearance
Habit / form
Rounded; Spreading
Texture
Medium
Foliage
Broadleaf Evergreen
Leaf color
Green
Leaf type
Simple
Leaf arrangement
Alternate
Leaf shape
Ovate
Leaf margin
Crenulate; Entire
Leaf feel
Smooth
Leaf size
3-6 inches long, 1-3 inches wide
Hairs present
No
Leaf detail
The evergreen leaves are ovate, 3 to 6 in long, and 1 3/4 to 3 wide, dark green above, lighter beneath, with minute, rounded teeth on the margins
Flower color
White
Flower value
Fragrant; Showy
Flower form
Raceme
Flower shape
Cross
Flower size
1-3 inches
Flower detail
Small, white, axillary flowers have 4 petals and are highly fragrant, singly or in clusters.
Bloom time
Spring; Winter
Fruit color
Gold/Yellow; Green; Pink
Fruit type
Berry
Fruit value
Edible; Fragrant; Long-lasting
Fruit size
> 3 inches long, > 3 inches wide
Fruit detail
The fruit is large and green when unripe, yellow when ripe often with patches of pink on the skin. It is extremely juicy.
Stem color
Green
Stem detail
New stem growth will be green. Contain thorns.
Wildlife & Ecology
Native status
Unknown
Distribution
All tropical, sub-tropical regions around the world
Attracts
Bees
Play value
Attractive Flowers; Colorful; Edible fruit; Fragrance
Food & Medicine
Edible parts
Fruit
Harvest time
Fall; Winter
Fruit type
Berry

Edibility

Fruit is eaten fresh or juiced or used to make jams, jellies or in baking.

Uses (ethnobotany)

The fruit is commonly used to make juices (fresh, canned, or dehydrated as powder, or concentrated and frozen) or used to make jams, and jellies. The peel is candied and used in cakes. It is also used as a source of pectin, used to preserve other fruits. An essential oil obtained from the peel is used as a flavoring in soft drinks, chewing gum, sweets, baked goods, ice cream. An oil can also be obtained from the seed that when refined, makes a good culinary oil.

Landscape Use
Landscape location
Container; Houseplants; Lawn
Landscape theme
Edible Garden
Design feature
Flowering Tree; Specimen
Garden tags
#glossy leaves #problem for dogs #problem for horses #problem for cats #tropical feel #edible fruits #edible #frost tender #houseplant #showy flowers #evergreen tree #yellow fruits #white flowers #medicinal #wet soils intolerant #container plant #full sun #fragrant flowers #shade intolerant #fragrant fruits #fragrant leaves #hortcontest #showy fruits
Problems & Resistance
Problems
Problem for Cats; Problem for Dogs; Problem for Horses
Resistant to
Heavy Shade; Wet Soil
Particularly resistant to
Drought tolerant when established.
Propagation
Grafting
Poison severity
Low
Poison symptoms
Vomiting, diarrhea, depression; potential dermatitis. The fruit is edible, skins and plant material can cause problems
Toxic principle
Essential oils and psoralens
Contact dermatitis
Yes
Toxicity summary
Low severity poison; contact dermatitis

Planted at Hunnicutt

Nobody’s planted this one yet.