Kumquat trees are slow growing trees, similar to shrubs. They have thick branches and are known for producing a delicious citrus fruit. These fruit trees make attractive landscape plants and also do well grown in containers. Their glossy evergreen leaves and fragrant white flowers appear in late spring, followed by fruit in fall. Kumquats are unique because the sweetest part of the fruit is the peel rather than the pulp. The fruit resemble a mandarin orange, but is smaller and oval.
A typical kumquat fruit tree rarely exceeds eight to ten feet in height, according to Floridadata.com. The tree’s leaves are roughly two to three inches long and the kumquat fruit is about the size of a small orange or plum. As these trees can produce about 8,000 pounds per acre, they provide a generous crop for growers.
History and Geography
The kumquat tree originated in China. In 1846 Robert Fortune of the London Horticulture Society introduced the kumquat tree to Europe. Later the tree came to North America and today is mostly grown in warm regions such as California, Louisiana and Florida. Besides the United States, kumquat trees continue to be cultivated in China, Japan and other areas of southeastern Asia.
There are several varieties of kumquat trees. The Hong Kong tree is a thorny variety that’s only grown as an ornamental pot plant in the western world, although it's cultivated for its fruit in China. The Marumi is slightly thorny with smaller leaves and produces fruit that’s somewhat more acidic than other varieties. The Nagami is the most cultivated variety in the United States. The Meiwa tree is an ornamental tree of dwarf size that’s mostly grown in China and Japan.
Kumquat trees are easy to grow as they're more cold-hardy than an average citrus tree and are drought tolerant. Their fruit grows at a height that's easy for picking. These trees are ideal for outdoor entertaining as fruit can be eaten right off the tree. The tree’s fruit contains vitamin C which is a powerful antioxidant. Its anti-inflammatory agents help lower asthma symptoms. Kumquats are also used in making jellies, preserves and marmalade.
Pests and Diseases
Container kumquats are vulnerable to mealybug infestations. Orchard trees may be subject to most pests attacking citrus trees, although they usually are immune to citrus canker. Other common pests include chewing insects and fruit flies. Common diseases are leaf spot, green scurf, greasy spot, fruit rot, anthracnose and scab infections.
Gardeners should be alerted for the giant swallowtail buttery which is a serious citrus tree pest. These butterflies are beautiful, but are a serious pest which lay eggs on kumquat trees, besides other citrus trees. Symptoms of a butterfly infestation are the caterpillars known as orangedogs whose presence can be detected by what appears as bird droppings.