Kumquat

Kumquats are small fruit-bearing trees that belong to the same family as oranges. They look like tiny oranges, about the size of a large olive. Kumquats grow naturally in southern China, but people also grow them in Japan and Southeast Asia. These trees can live in cooler weather better than many other citrus trees.

Scientists sometimes have different ideas about how to group kumquats. In the past, they were called Fortunella, but now they are usually part of the Citrus group. Recent studies show there are three main types of kumquat trees.

Etymology

The word "kumquat" comes from the Cantonese language. In Cantonese, it is called gām gwāt, meaning "golden orange." This name describes the fruit's lovely golden color and orange look.

Description

Kumquat plants have smooth branches and very shiny leaves. They grow pretty flowers that are white and appear in groups or alone on the leaves. These plants can grow to be about 2.5 to 4.5 meters (8 to 15 feet) tall, with thick branches that sometimes have tiny thorns.

They make small, yellow-orange fruits that are oval or round. These fruits are about 2.5–5 centimeters (1–2 inches) wide. The skin of the fruit is sweet, and the inside is a bit sour. People enjoy eating the whole fruit for its mix of sweet and sour tastes. Kumquat trees can make their own fruit without needing help from another tree (self-pollinating).

Species

Scientists are still learning how to group kumquats. Some think all kumquats belong to one group. Others think there are several groups. In the past, kumquats were grouped with oranges. Now, some scientists think they should have their own special group.

A study in 2022 looked at many types of kumquats. It found reasons to split them into two main groups. One group has a wild type from Hong Kong. The other group includes the types people usually grow. Inside this group, there are several types that are very different from each other.

Hybrids

Main article: Citrofortunella

Kumquats can mix with other fruits to make new types, called hybrids. Some of these include:

• Calamansi: made from a mandarin orange and a kumquat
• Citrangequat: made from a citrange and a kumquat
• Limequat: made from a key lime and a kumquat
• Mandarinquat: made from a Satsuma mandarin and a kumquat
• Procimequat: made from a limequat and a kumquat
• Sunquat: made from a Meyer lemon (maybe) and a kumquat
• Yuzuquat: made from a yuzu and a kumquat

Origin and distribution

The kumquat tree comes from southern China. People in China first wrote about kumquats a long time ago. For many years, people have grown kumquats in East Asia, South Asia, and Southeast Asia. In 1846, a man named Robert Fortune brought kumquats to Europe for the London Horticultural Society. Since then, people grow them all around the world.

Cultivation

Kumquats are tougher than other citrus fruits like oranges. The best time to plant seeds is in spring because the weather is nice, with more rain and sunshine. This gives the tree time to grow well before winter. Early spring is also the best time to move a small tree to a new spot. Kumquats need plenty of sunlight, about 6 to 7 hours a day, and grow best when planted directly in the ground. They grow well in warm places, such as USDA hardy zones 9 and 10, and can survive very cold temperatures, as low as 18 degrees Fahrenheit (−8 degrees Celsius). When trees are old enough, kumquats will grow in about 90 days.

In the UK, Citrus japonica has received a special award from the Royal Horticultural Society for being a good garden plant.

Kumquats do not grow well from seeds, so they are usually grown using parts of another citrus plant, special cutting methods, or pieces taken from other trees.

The Nordmann seedless is a type of Nagami kumquat without seeds. It looks similar to Nagami but has a slightly different shape and lighter skin.

The C_entennial Variegated_ is another type of Nagami kumquat. Its fruits change color from striped light green and yellow when not ripe to orange when ripe. These fruits are oval-shaped, about 2.5 inches long, and have smooth skin. They ripen in winter. This type produces more fruit compared to its skin and has rounder fruits that sometimes have a neck. The fruits can be recognized by their bright green and yellow stripes and lack of thorns.

The Puchimaru kumquat is a Japanese type that usually has no seeds. It resists certain plant diseases. The fruit weighs between 11 and 20 grams and is shaped like an oval. It has a dark orange skin that is 4 millimeters thick. The juice inside is not very much, and the oil spots on the skin are large and easy to see. The fruit ripens in January.

Uses

Kumquats are mostly water, with some carbohydrates, protein, and a little fat. They give you vitamin C and have energy you can eat.

The skin of a kumquat has special oils that give the fruit its smell and flavor. These oils include limonene and a few other compounds that make the kumquat taste spicy and a bit woody. There are also some other chemicals that help give kumquat its unique taste.