Latest Detailed Guide to Making Broadleaf Mahonia Bonsai

There are many varieties of broadleaf Mahonia, common ones include the densely spined broadleaf Mahonia, whose leaf margins have denser spines; the spineless broadleaf Mahonia, whose leaf margins have no spines, and other varieties, which are also often used to make bonsai. Mahonia has clustered stems, spreading branches and foliage, and variable leaf shapes, and stays evergreen all year round. Especially when the old leaves turn orange-red and contrast with the newly sprouted emerald leaves, the red and green set each other off and look very beautiful and elegant. It is a foliage bonsai suitable for appreciation in all four seasons, and it also has the effect of flowers and fruit for viewing.

Propagation and material collection:

Mahonia can be propagated by cuttings, division or sowing. Cutting propagation is divided into hardwood cuttings and softwood cuttings. Hardwood cuttings should be done in early spring in March. Cut 1- to 2-year-old healthy branches as cuttings, 20 cm long, insert them as soon as they are cut, in a semi-shaded place with moist and loose soil, or insert them into plain sand or vermiculite. Softwood cuttings can be done during the plum rain season. Cut fully developed but not yet lignified semi-mature branches of the current year as cuttings, 15 cm long, insert them in a sandy soil seedbed, with a depth of 12 to 23 cm of the cutting. When inserting, first make holes in the seedbed with a bamboo chopstick, then insert the cutting, press the base firmly with your fingers so that the soil fits closely around the cutting, water thoroughly, and build a shade frame. In dry weather and high temperatures, water frequently, spraying with a fine-hole watering can in the morning and evening to keep the soil moist. Roots and shoots will form in about 50 days, and they can be transplanted the following spring to grow larger seedlings.

Mahonia often grows wild in thickets under forests by mountain streams. You can select old stumps with peculiar roots and trunks to dig up, cut the branches and trunks, and first plant them in the ground for growing out the stock. After new branches and leaves sprout, pot them the following spring for processing. In this way the trunk is thick and short, with many branches and an elegant posture, and can be made into a beautiful foliage bonsai.

Planting:

Before planting, soak the plant in clean water for about half an hour to increase the survival rate. When planting, it is best to coat the roots and stems with mud paste, then plant in loose, breathable sandy soil. Afterward, keep the soil moist but not waterlogged, and spray the plant frequently to increase air humidity and ensure survival. In not much time, many new buds will grow at the bud eyes. You can choose a few strong buds in ideal positions to keep, and wipe off the rest. Afterward, strengthen water and fertilizer management to make the plant grow vigorously. In the spring of the second year, appropriately shorten the branches that sprouted the previous year to encourage new healthy branches.

During the process of making broadleaf Mahonia bonsai, you can also cultivate directional buds. The method is that when a certain part of the plant needs a bud, spray it with water frequently, and before long a new bud will grow at that position.

Pruning:

Broadleaf Mahonia grows rapidly. After 2 to 3 years of cultivation, the branches and trunk can be shortened, and some declining leaves should also be removed in time to keep the tree shape beautiful. If it is not cultivated as a fruit-viewing bonsai, remove the spent flowers after blooming to avoid consuming too many nutrients and affecting growth.

Shaping:

Broadleaf Mahonia can be processed into different forms of bonsai, such as forest style, double-trunk style, single-trunk style, slanting-trunk style, waterside style, and cliff style. The shaping method is mainly pruning, with wiring as a supplement. Wiring should be done after the new branches have lignified, because at that time the branches are more flexible and not easy to break, while new branches are soft and brittle and very easy to break, so they are not wired for shaping. The main trunk and old branches are relatively brittle and hard, so they can only be pulled or appropriately twisted into shape with metal wire or palm fiber within a certain range, to avoid breaking the branches and trunk. Because its leaves are relatively large, the crown mostly uses a natural style to express its free and spreading natural beauty.

The processing of Mahonia bonsai is similar to that of nandina, mainly by pruning and combined planting, and generally not by wiring. Processing should be done before sprouting in spring, so that the branches and leaves are uneven up and down, well spaced and layered. As for tree shapes, the multi-trunk-from-one-root style and the exposed-root style are the most common, and there are also the combined planting style and the straight-trunk style. The multi-trunk-from-one-root style and combined planting style must pay attention to changes in height, density and front-to-back arrangement. For the exposed-root style, you can appropriately raise the main root when planting, pile soil on the pot surface, and then gradually remove the piled soil when watering so that the roots are exposed.

Repotting:

Repot once every spring before budding. The potting soil should be sandy soil rich in humus, loose and breathable, with good drainage.