Osmanthus fragrans is evergreen all the year round, with lush branches and leaves, blooming in autumn and overflowing with fragrance, which is widely used in gardens.
Osmanthus fragrans is often planted on both sides of roads, beside rockeries and in pavilions in gardens. It can also be planted in clusters to form landscapes such as Guihua Mountain, Guihua Slope and Guihua Ridge. It can also be planted with autumn leaves, which is fragrant in color and is an excellent tree species embellishing autumn scenery; If two osmanthus trees are planted in front of the courtyard, that is, two osmanthus trees in the courtyard, it is the traditional configuration method of osmanthus.
Osmanthus fragrans is an evergreen shrub to a small tree, with a height of12m, gray bark and no cracks.
Herbaceous leaves, long oval, 4 ~ 12 cm long, sharp or tapering at the top, wedge-shaped at the base, serrated on the whole or upper part.
Flowers clustered in axils or cymes; The flowers are small, yellow and white, and fragrant.
Drupe oval, purple-black after maturity.
Flowering: September ~ 65438+ 10.
There are many varieties, which are generally divided into 4 groups: Jingui group, with light yellow to dark yellow flowers and strong aroma; The flowers in Yin Gui group are nearly white or light yellow with strong fragrance; In the Dangui group, the flowers are orange-yellow or orange-red, and the fragrance is light; In the Sijigui group, the flowers are nearly white or yellow, which bloom several times a year and have a faint fragrance.
Osmanthus fragrans likes light and is slightly resistant to shade; Like warm and ventilated environment, not cold-resistant; Prefer moist sandy loam with good drainage, avoid waterlogging land, saline-alkali land and heavy clay.
Osmanthus fragrans is a pseudo-branched branch with strong dryness, weak stratification and round crown.
The buds are terminal or lateral, all overlapping buds.
Adult trees shoot new shoots once a year, and generally do not shoot summer shoots or autumn shoots.
Young trees, especially young seedlings, tend to branch twice when the fertilizer and water are sufficient and the temperature is suitable.
The buds at the lower part of the branches generally do not germinate and become hidden buds.
The cryptobud has a long life. After one or several years, if the environmental conditions are suitable, it can sprout and branch, which is the basis of renewing the crown and one of the important reasons for the longevity of osmanthus fragrans.
Osmanthus fragrans has the habit of flowering in batches. Except osmanthus fragrans and laurel trees, the general varieties bloom twice a year. In most years, the first batch of flowers is less, and the second batch of flowers is more.
From June to August of that year, the flower bud differentiated, and it was a pure flower bud, which was born in the axils of branches and leaves of that year. Buds overlap between leaf axils, with the upper differentiated first and the lower differentiated or undifferentiated later.
Osmanthus fragrans is mainly planted with short branches. Therefore, in pruning, in addition to the need to retract and update because of the weak tree potential and branch potential, it should be mainly drained to overcome the over-dense branches outside the crown and affect the ventilation and light transmission in the crown.
Cut as little or no as possible, but also prevent short cutting from being too heavy, stimulate the growth of new shoots, reduce the number of flower buds and affect flowering.
Varieties with strong dryness, such as Jingui and Dangui, usually adopt the plastic way of middle-dry layered shape.
In the seedling stage, a robust and upright branch is selected as the trunk, all other unsuccessful branches are thinned out, the selected branch is lightly cut, and a robust bud is left after cutting, and another opposite bud is wiped off at the same time, so as to ensure that only one new shoot is used as an extension branch of the trunk in the coming year.
In order to maintain the advantage of the trunk, the second and third pairs of cut buds should be erased to control the growth of competitive branches.
After planting, leave the trunk with a height of 40 ~ 60 cm, and choose 3 ~ 4 branches with similar size, uniform distribution around and opening angle of about 45 as the first layer of main branches.
The spacing between the main branches is about10 ~15 cm; At the same time, we should choose healthy branches that grow vertically, make them grow upward, cultivate them into middle stems, and remove redundant branches and roots in time.
Then, choose a main branch 40 ~ 50 cm away from the last main branch of the first floor on the middle trunk, choose another main branch 20 ~ 30 cm away from this main branch, and so on until the whole tree has 5 ~ 7 main branches.
However, it should be noted that the main branches of each layer cannot overlap.
On the main branch, branches with vigorous growth and suitable positions are selected as side branches, the distance between the first side branch and the middle trunk is 40-50 cm, and then the second and third side branches are selected every 30-50 cm.
However, it should be noted that the side branches of the same level in the same layer must be selected on the same side of the main branch to avoid crossing each other.
This kind of tree, the crown is ventilated and transparent, the inner chamber is not empty, and the crown is high and round.
Varieties with weak dryness, such as cinnamon, usually have a round head and a trunk.
After planting, leave a trunk with a height of 40 ~ 60 cm, and choose 5 ~ 7 main branches on it. Each main branch is evenly distributed on the trunk, cut off the middle trunk, and then select several side branches on each main branch. The selection and retention of lateral branches are basically the same as the layered shape of the trunk.
This kind of tree conforms to the natural growth characteristics of osmanthus fragrans, with simple shape, light pruning, rapid crown expansion and early flowering, but the crown is easy to close, and the ventilation and light transmission in the inner room are poor, so attention should be paid to thinning the dense branches around it in time.
Maintenance and pruning is mainly based on thinning, generally not short cutting, generally can not be re-cut, so as not to stimulate the growth of waste.
Except for a few miscellaneous branches, the pruning objects are mainly autumn shoots and too many secondary branches. The general practice is to "see five to two, see three to one", that is, trim the dense parts, and the amount of pruning should be small.
Attention should be paid to keeping the spring shoots that grow vigorously and stop early, so as to facilitate the next year's flowering.
At the same time of maintenance and pruning, we should pay attention to the uniform distribution of all kinds of branches and keep the crown properly enriched.
Generally speaking, the upper part of the crown is pruned strongly and the lower part is pruned weakly to balance the tree potential.
If you want to control the expansion of the tree, you can take back the long branches by changing the head, but be careful not to take back too much at a time.
Most of the old osmanthus trees are aging, with short growth of new shoots and few flowers.
The main task of pruning is to update and update.
The following measures can be taken: retracting the backbone branches, restraining the former and promoting the latter, promoting the middle and lower parts to sprout new branches and increasing the amount of branches and leaves; Shrinking and shearing elongated "bare branches"; Thinning the dense branches on the periphery; The short and tender branches in the inner chamber promote the germination of new buds in the inner chamber, form flower buds and continue to bloom.