The Latest Cultivation Techniques and Methods Tutorial for Kumquat

Variety Classification of Kumquat

Kumquat is generally divided into two types: common kumquat and smooth-skinned kumquat. Let's first take a look at how these two types of kumquat differ!

1. Kumquat

Kumquat (including names such as Huoyan, Jin, Mi, Xiu, Jinkan, Jindan, Jinzao, etc.) belongs to the Rutaceae family. It is a thorny evergreen shrub with a tree height of more than 1 m, reaching a maximum of 4 m. The crown diameter is about more than 2 m. The branches are round, slightly angular, with short internodes, about 1 cm between 9 nodes. The thorns are 3.2-3.8 cm long, sharp-tipped, yellow, growing horizontally, and emerging from beneath the leaves. The leaves are alternate and rather densely arranged. The leaf tips of new leaves have slight blunt serrations, the petioles are short, with narrow wings. The flowers are white, with 5 petals, and the calyx is narrow and small. The flowering period is from June to September. The first flowers appear around Grain in Ear: the second flowering occurs from Summer Solstice to Grain Full: the third flowering occurs at Minor Heat and Major Heat; the fourth and fifth flowering occur around the Beginning of Autumn. Flowering does not end until after fruit set. The kumquat fruit generally begins to ripen in mid-October and enters the picking period.

The fruit is elliptical and round, with a fruit diameter of 2.49—3.2 cm and a fruit height (length) of 2.73——3.35 cm. The middle of the fruit is plump, tapering toward both ends, the fruit top is smooth, the stem end is slightly concave, with slight grooves, and the stylar point is quite small. When ripe, it is glossy and shiny, and the fruit is yellow-green or golden yellow. The cross-section of the fruit has a fragrant aroma, and the peel thickness is 4-5 mm. The oil cells are light orange. The peel and flesh are difficult to separate, and the flesh is juicy, sweet and sour, and delicious. Each fruit contains 5-8 seeds, and each kumquat tree produces 8-10 kg of fruit.

① Seedling trees begin to flower and bear fruit in 5-6 years and can produce for 40-50 years, with some producing for 100 years.

② Grafted seedlings begin to flower and bear fruit in 3-5 years, bearing fruit earlier than seedling trees. Earlier income. Layered seedlings are basically similar to grafted seedlings.

2. Smooth-skinned kumquat

Smooth-skinned kumquat is a newly developed superior variety. The smooth-skinned kumquat tree has an upright posture, a tree height of 1.5—2 m, a crown diameter of several meters, a trunk circumference of 40 cm, and a trunk height of 1.8 m. It is smooth and thornless, grayish-brown, and the vegetative branches are slender, soft, slightly drooping, and smooth. The leaves are whorled, elliptical-lanceolate, 6.3—6.5 cm long and 2—3.1 cm wide, with a petiole 1.1 cm long. The leaf is entirely green, with a bluntly pointed tip, and the leaf curls inward like a boat shape. The basal 1/3 of the leaf is wavy, the upper leaf surface is dark green, and the lower leaf surface is light green, with the midrib raised and the lateral and reticulate veins obvious. The flowers are white, with 3—6 petals, mostly 5 petals, spoon-shaped, 1.12 cm long and 0.42 cm wide, with the tip oil gland not obvious and smooth. The pedicel is 0.53 cm long, and when open, the petals reflex outward to a large degree. The flowering period is 3—5 days earlier than that of common kumquat, with 3—4 flushes of bloom from June to August.

The fruit is nearly spherical or elliptical, and the peel oil cells are sparse, fine, and smooth. The individual fruit is large and heavy, with large ones weighing 23.6 g. The flesh is firm, yellow-white, with soluble solids above 20%, and the fruit tastes sweet and crisp, without a sour or spicy taste. The skin is thin but tough, and it stores better than common kumquat. The ripening period is from November to January of the following year.

Kumquat Planting Environment Requirements

1. Growth habits

The kumquat tree is a neutral tree species. During the seedling stage and young forest stage, it is neutral and slightly shade-loving; after the forest is established, it is neutral and slightly sun-loving. It prefers a warm and humid climate, likes fertilizer, fears waterlogging, and avoids drought. Excessive light and exposure can easily cause sunscald. When planting in mountainous areas, north-facing, northeast-facing, or southeast-facing sites are preferable. It adapts to a wide range of soil pH, with slightly acidic soil of 5.5—6.5 being most suitable. It has strong cold resistance. It grows quickly. A two-year-old seedling tree can reach 60-70 cm in height.

① Shoot growth: spring shoots sprout from late April to early May, lasting 25—28 days; summer shoots sprout in late June and stop in mid-July, lasting 25 days—28 days. Autumn shoots sprout in mid-August and stop in mid-to-late September, lasting 30 days.

② Flowering period: the first flowering is in mid-to-late June; the second flowering is in mid-to-late July; the third flowering period is in mid-to-late August; the fourth flowering is from early September to October; it takes about 150—170 days from flowering to fruit ripening. 

2. Growing soil environment

Kumquat is suitable for planting in mountainous areas. Hilly, low-mountain, and mid-mountain zones at an altitude of 200-500 m are especially good, with river valley areas being best, because these areas are surrounded by high mountains and ridges that block cold air currents and can prevent low temperatures and wind damage. The kumquat tree is a mycorrhizal plant, and its root system also has the characteristics of liking aeration, fertilizer, and moisture. Therefore, the land for planting kumquat groves should preferably be black sandy soil or yellow sandy soil with strong water and fertilizer retention, relatively high natural fertility, and a fairly deep soil layer, so as to promote the development and growth of the kumquat grove's mycorrhizae.

3. Climatic conditions required for kumquat growth

① Temperature: The kumquat grove requires a mild climate, with an average annual temperature of 19°C. The hottest month is July, with a monthly average temperature of 27.9°C; the coldest is January, with a monthly average temperature of 8.5°C. Over the past 30 years, the county's extreme maximum temperature was 38.6°C (January 1971), and the extreme minimum temperature was minus 5.5°C (January 1963). The average frost-free period is 290 days. No kumquat groves have been found to suffer damage from high temperatures or freezing.

② Rainfall: The average annual total rainfall is 1942.5 cm. June rainfall accounts for nearly 20% of the annual rainfall, while December or January rainfall accounts for only 2.5—2.6% of the annual rainfall. No phenomenon of poor kumquat harvest caused by too little rainfall has been found either.

③ Humidity: If air humidity is too high, the kumquat fruit contains more water and the peel is delicate. Conversely, if the air is too dry, it will cause poor development of the kumquat fruit, resulting in small fruit, thick peel, bland flesh, and poor quality. During the flowering and fruiting period of kumquat, a humidity above 80% is more suitable.

④ Sunshine hours: The total annual sunshine hours are 1416.3 hours, accounting for 32% of the local possible sunshine hours. There are more sunshine hours in summer and autumn and fewer in winter and spring. Summer is 502.2 hours, autumn is 47.4 hours, winter is 214.3 hours, and spring is 228.4 hours. For high yield and good quality of kumquat, it is better to have relatively abundant sunshine in spring and autumn and not too intense direct sunlight in summer.