Production of boxwood bonsai

(1) Botanical knowledge

Belongs to Populus tomentosa family, Populus tomentosa. Evergreen shrubs or small trees, dense branches, branchlets quadrangular, branches and leaves towering on clusters. Leaves opposite, leathery, elliptic or Obovate, apex rounded or retuse, base cuneate, surface bright green, abaxially yellowish green. Flowers clustered in leaf axils or branches, blooming in April, yellowish green. Capsule ovoid. Main species and varieties

1. Populus tomentosa, also known as Populus tomentosa. Evergreen dwarf shrubs, densely branched. Leaves opposite, leathery, spatulate or oblanceolate, surface dark green, glossy.

2. Populus tomentosa, also known as Pearl boxwood. Small evergreen shrub with dense branches and leaves, short internodes, small leaves and glossy leaves. The tree is graceful and is a precious tree species for making bonsai.

Populus tomentosa is produced in the provinces of central China and is wild in the mountains below 1300 meters above sea level. More gardens or potted plants are planted in the Yangtze River basin and its south for ornamental use.

Like light, but also slightly shade-resistant, more cold-resistant, suitable for fertile, moist, loose places, acidic soil, neutral soil or slightly alkaline soil can adapt. Slow growth, strong germination and resistance to pruning.

(2) material selection and cultivation measures

Artificial propagation: usually propagated by sowing or cutting. Sowing should be in July to harvest ripe fruit, spread out and dry, threshing and seed collection, bag storage. If sowing in winter or early spring, if sowing later than March, few seedlings will emerge in that year, and most of them will not germinate until the next year. Before sowing, soak the seeds in 40 ℃ warm water for one day and night (natural cooling) to dry, then sow the seeds. The seedbed soil should choose fertile and loose sandy loam, the row spacing of strip sowing is 1520 cm, the sowing width is 5 cm, the depth of sowing ditch is 2 cm, the thickness of coke mud is 1 cm after sowing, and then cover straw. After the seedlings are unearthed, uncover the grass in time and build a shed for shade. At the seedling stage, we should strengthen management, weed and loosen the soil, water frequently, keep the soil moist, and apply thin pancake fertilizer and water. Remove the shade shed in September, leave the bed for a year and then plant it separately.

Cutting propagation: appropriate in the plum rain season, select semi-lignified sturdy branches as cuttings, length 10: 12 cm, base with heel, upper leaves 5: 6 pairs, deep 1B2~2B3, plant spacing 6 × 10 cm, solid soil after planting, watering thoroughly, building shade, often spraying water to keep the soil moist, especially in summer. Remove the shade shed from September to October, leave the bed for a year and then plant it separately. Populus tomentosa can also be used to cut thick branches from tufted plants, leaving several plates of branches and leaves above, bury all the cadres in yellow sandy soil or vermiculite, expose the branches and leaves, often water to keep moist, and take root after half a year.

Mountain mining: subtropical mountain boxwood is scattered under the forest or by the forest edge ditch. In the barren land with bare rocks, boxwood grows short, branches and leaves are dense, and potted plants are dug and processed into bonsai products. Populus tomentosa grows in pieces in the upper part of Zhongshan at an altitude of 1300 to 1800 meters in East China, forming evergreen shrubs dominated by Populus tomentosa. It also grows in the cracks in the rocks, with thick and short stem, dense branches and small leaves, which is most suitable for making bonsai. However, fish scale yellow poplar is an alpine tree species, which requires a cool and moist climate, acid sandy loam, excavated wild tree stumps or saplings, should bring more mountain mud to live in the soil, and often spray water, and can be fertilized with thin pancakes and mixed with a small amount of ferrous sulfate. In summer, it is better to put it in the shade or in the shade of the trees, and it is better to put the pot on the wet sand.

(3) the process of potting.

Select basin: Huang Yang should use purple sand pottery basin or glazed pottery basin, the shape of the basin is mostly rectangular or oval in the middle depth, and the cliff type should use a deep thousand-cylinder basin. The basin color should be purple or light yellow to highlight the green branches and leaves.

Use soil: yellow poplar likes fertile and loose loam, slightly acidic soil or slightly alkaline soil can adapt, and can also grow in calcareous soil. Pot culture can use mature pastoral soil or rotten leaf soil mixed with appropriate amount of rice chaff ash.

Planting: generally carried out before sprouting in spring, the root that is too long and too dense should be trimmed properly so as not to make the root nest bend in the basin.

(4) Positioning techniques

Processing: the old stumps of boxwood excavated in the mountains usually begin to be processed after 1 or 2 years of cultivation, while the seedlings cultivated since childhood can not be processed until 3 or 4 years later. The shape is mainly climbing, and it can also be roughly tied and cut. Populus tomentosa branches are hard and thin, climbing should not use wire, it is best to use brown wire. The climbing period is mostly in spring, and pruning can be carried out at any time.

Tree shape: yellow poplar should be inclined dry type, curved dry type and cliff type, etc. In the traditional form of "Yang Pai" bonsai, the branches and leaves of Populus tomentosa are made into "cloud sheet" by "fine binding and fine cutting", while in "Su School" bonsai, "steamed bread" is made by "coarse binding and fine cutting", each with its own characteristics. Boxwood is strong in germination and resistant to pruning, and it can also be processed into a natural tree shape by pruning. If the boxwood bonsai is matched with a beautiful stone, it will become "boxwood", so that the boxwood with an old tree and a small one will be born near the stone, making its state more natural and wonderful.