Detailed Explanation of the Methods and Techniques for Making a Kumquat Bonsai

Kumquats can be propagated by cuttings or grafting. For grafting propagation, citron or trifoliate orange is mostly used as the rootstock, and vigorous-growing kumquat branches are selected as the scion, using approach grafting, which roots easily. Cutting propagation can be carried out from April to June, and the cutting temperature should be above 20%. Cuttings are cut into 7-10 cm lengths, retaining 1-2 leaf stalks, with most of the leaf blade left on the stalk; the upper end of the cutting must be sealed with wax, cutting and inserting as you go. The soil used for pot cuttings should preferably be sandy loam that has been boiled and sterilized. If cuttings are taken in April-May, the cuttings should be inserted 3/5 into the soil, with half shade; if cuttings are taken in June, the cuttings should be inserted 2/5 into the soil, with full shade. After insertion, water once thoroughly, and cover the pot opening with plastic film to prevent rain and stray bacteria from entering, which can keep the cuttings moist. Every half month, uncover the film for ventilation once, check the degree of dryness and moisture of the potting soil, and water as appropriate. It takes about 60 days for the cuttings to root and sprout after insertion. After the cuttings have leafed out, remove the film, and once new branches and leaves have sprouted, move them to pots for final planting. The survival rate of cuttings can reach over 80%.

Cuttings or grafted seedlings that have been cultivated for 3-5 years can be potted after Qingming. The pot should preferably be a slightly larger clay pot or ceramic pot. The potting soil should be loose, breathable, fertile, and water-retentive, with humus soil being the best. When potting, apply sufficient fully rotted cake fertilizer or human manure and urine, etc., into the potting soil. Artificial culture soil can also be used, that is, mix 4 parts vegetable garden soil, 2 parts leaf mold, 1 part raw soil, 1 part fine sand, 1 part coal cinder, and 1 part fully rotted cake fertilizer evenly; after planting, water once thoroughly, shorten the branch tips, remove the weak and keep the strong, to promote the growth of vigorous new shoots in the future, control the tree shape, and maintain a beautiful tree posture. Adopting the above measures can promote fruit setting after flowering and prolong the fruit-hanging time.

The maintenance and management work is as follows.

1. Watering. Water kumquats by the principle of seeing dry and seeing wet. When the soil surface is white and hard, and wet soil is only seen 1-2 cm deep, then it can be watered, thoroughly at one time. Do not water heavily every day; if water accumulates, the roots will rot. In dry summer and autumn seasons, water once a day, and also spray the leaves and sprinkle water on the ground. After entering winter, control water to keep the potting soil on the dry side. When flower buds begin to appear, reduce watering; when the flower buds change from green to white, resume normal watering to protect flowers and fruit. Kumquats like acidic soil and acidic water; watering with fermented rice-washing water gives good results. If yellow leaves appear, you can use green leaf essence or ferrous sulfate solution to water or spray the leaves.

2. Fertilizing. Kumquats like fertilizer; the potting soil should be given sufficient base fertilizer to encourage new shoots to produce more new buds. During the bud stage, water with organic liquid fertilizer once a week. After the flowers fall, apply a phosphorus and potassium liquid fertilizer once more to promote large and evenly shaped fruit. Kumquat fruits mostly fall in early winter; to prolong the fruit-hanging time, all the first-opening flowers can be removed, let the potting soil dry slightly, and when the leaves slightly show a wilting state, then water and fertilize sufficiently; in early June of the lunar calendar, flower buds can reappear; after fruiting, until the Spring Festival, the kumquat still hangs all over the branches. From flowering to fruit ripening, kumquats consume a large amount of nutrients; to ensure normal flowering and fruiting the following year, apply base fertilizer twice throughout winter until the Spring Equinox. After entering Minor Snow, apply sufficient fruit-preserving fertilizer; dig a ring-shaped trench 3-5 cm deep around the potting soil, and bury fermented cake fertilizer into the ring-shaped trench, 150-250 grams per pot for large plants, and 100-150 grams per pot for small plants. Before the Spring Equinox of the following year, heavily apply a solid sprout-promoting fertilizer once, by the same method, and water after applying.

3. Placement location. Kumquat growth has a special directional nature and stability, so do not arbitrarily change the placement direction of the bonsai. When kumquats set fruit, it coincides with the windy season, so they should be moved to the base of a windproof wall, or a windbreak should be set up for the flower pot. In the hot summer season, kumquats should be shaded. In winter, in the Jiangnan region, they can overwinter outdoors, but cold-resistant and freeze-proof measures should be taken, such as: placing them on a south-facing balcony; do not apply nitrogen fertilizer after October; block the wind when dry cold winds blow; in winter and early spring, when continuous sunny frost weather occurs, wrap the kumquat pot with newspaper or woven bags from night to early morning. In certain years, when continuous severe freezing weather occurs or in northern regions, kumquats should overwinter indoors instead. After mid-October, they should be moved indoors for maintenance at 10°C, and only taken outside after mid-May of the following year.

4. Pest and disease control. The main pests and diseases of kumquats include scale insects, red spiders, aphids, citrus swallowtail butterfly larvae, as well as powdery mildew, sooty mold, and canker. Scale insects can be brushed off with a small brush, caught on paper, and burned. Aphids and red spiders can be sprayed with 100-400 times machine oil emulsion or liquid boiled from garlic and onion, and can also be killed by spraying with dimethoate solution. From May to October, citrus swallowtail butterfly larvae often harm kumquat leaves; they can be poisoned with 1200 times 80% dichlorvos emulsifiable concentrate, and pupae can also be caught and larvae killed. Powdery mildew, sooty mold, and canker can be sprayed with carbendazim, with good control results.