How to prune a Chaenomeles speciosa (flowering quince) bonsai? Detailed technical points
Chaenomeles speciosa has a strong tree vigor, strong sprouting ability, a tree shape that easily becomes disordered, and tolerates pruning. Its flower buds belong to the summer-autumn differentiation type, with July to August being the concentrated flower bud differentiation period. On well-grown two-year-old branches, the axillary buds in the middle and lower parts of the spring shoot often differentiate into flower buds, blooming the following spring and forming flowering spurs. On well-developed oblique two-year-old side branches, almost all axillary buds except those at the tip can differentiate into flower buds. The tips of short shoots on perennial branches and well-grown axillary buds can also differentiate into flower buds. Therefore, when pruning, it is essential to promote the growth of many flowering spurs and to retain a certain number of mother branches.
It is best to prune in early spring before the tree body begins to sprout, and the pruning methods are mainly heading back and thinning out. Chaenomeles speciosa has a strong ability to produce root suckers, and every year many suckers sprout from the base of the plant. You can select and retain 2-3 thick, strong sucker branches and head them back to keep as renewal branches, while thinning out 2-3 old branches each year. In this way, renewal branches are retained and aged branches are removed every year, which can keep the number of branches within the clump constant. Repeated pruning in this way can keep the shrub vigorous for a longer time, blooming continuously and greatly improving its ornamental value.
Pruning of Chaenomeles speciosa generally adopts thinning during the dormant season, and pinching and heading back of overly long branches during the growing season. During dormant-season pruning, cut away 1/3 of overly long branches, and at the same time remove dead branches, diseased and pest-infested branches, overly dense branches, crossing branches and thin, weak branches one by one, with the aim of improving ventilation and light penetration within the shrub and avoiding dense branches that affect growth. After flowering, head back overly long branches to stimulate new growth and prevent the lower parts of the branches from becoming bare. During the growing season, keep 2/3 to 1/2 of new shoots and cut off the shoot tips, or pinch out the tips when new shoots grow to 60-80 cm, especially for upright shoots, in order to inhibit tip growth, control excessive elongation of one-year-old branches, promote flower bud formation in the middle and lower parts, and prevent bare-leg phenomenon.[Post-bloom pruning]
In order to maintain the tree shape and make the overall effect beautiful, appropriate pruning is needed after flowering. Two weeks after flowering, thin out crowded branches on the plant and branches protruding beyond the crown outline. Appropriately head back long branches, leaving 3 to 4 buds from the base and cutting off the rest, which helps increase the formation of flowering spurs. Fruits set after flowering should be removed as early as possible to avoid nutrient loss that would affect flower bud formation the following year.
[Precautions]
1. When heading back flowering branches to control plant height, do it lightly and carry it out year by year, to avoid heavy heading back affecting the amount of spring bloom.
2. The number of branches retained should be determined by the amount of space. When planting a single specimen, more branches can be retained; when planted in rows or in masses and space is smaller, fewer branches can be retained.
3. Post-bloom pruning removes leafy branches, reducing the photosynthetic area, which will inhibit plant growth, so pruning should be light.
When pruning, also note the following:
1. During pruning, thin out overly dense branches, diseased and pest-infested branches, and crossing branches.
2. Pay attention to the renewal of flowering branches. In actual practice, there are some mistaken tendencies. One is the belief that Chaenomeles speciosa blooms on old branches, so all new shoots should be thinned out. Branches 3 to 5 years old produce the most flowers. Therefore, one should not simply retain old branches and thin out new ones.
The correct method is:
Renew flowering branches year by year so that the plant always remains in a state of full bloom. Generally, renew 2 to 3 flowering branches per year, and excess new shoots can be thinned out.
Another practice is to pay no attention to new shoots and let them grow naturally. Doing so very easily disrupts the tree shape, making branches thin and dense, which not only fails to provide ventilation and light penetration but also often causes outbreaks of pests and diseases, and greatly affects flower quality. For one-year-old branches, each year from after leaf fall to before bud break, in addition to thinning out thin and weak branches, keep 2/3 to 1/2 of all new branches and cut off the shoot tips.