How to trim the dormant period of peony? Dormant pruning of tree peony

How to trim the dormant period of peony? Dormant pruning of tree peony

1 present situation of growth and application of tree peony in Beijing area

Peony has been cultivated in China for more than 1500 years, and it is a valuable characteristic flower in our country. The cultivation of peony in Beijing has a long history, which flourished day by day after the establishment of the capital of Liao and Jin, and reached its peak in the Ming Dynasty.

Although the old capital of famous gardens in Beijing no longer exists, peony is widely used in gardens, often used in plant landscape construction, living alone in the capital. Since ancient times, there has been a saying of "planting flowers for one year and watching flowers for ten days". In order to make better use of peony in garden plant landscape, in addition to cultivating new varieties of excellent quality, attention should also be paid to cultivation and conservation techniques to make peony create more beautiful scenery in a short flowering period. Among them, because peony is a perennial shrub, the root is highly tillering. The departure or retention of the new strip and how to prune the old one have become the most important links in the cultivation and maintenance of peony.

2 the growth habits of tree peony

Peony is a perennial deciduous shrub with a height of 1m to 2m, short branches, thick and brittle stems, green branches and grayish brown old stems, flowers born at the top of branches in the same year, solitary, large and beautiful flowers, with red, pink, purple, white, yellow and green flowers. Have like cool, avoid heat, like light characteristics, slightly resistant to shade, more resistant to cold. Require loose, fertile, well-drained neutral loam or sandy loam, avoid heavy clayey soil or low-lying water planting.

The bud of peony is covered by 6-8 scales, so the bud of peony is also called "scale bud". Tree peony overwinters with scale buds, which can be divided into flower buds, leaf buds, latent buds and adventitious buds according to their function and degree of differentiation.

Among them, the flower bud of peony is a mixed bud, which can branch, grow leaves and blossom. The one born at the top of the branch is called the "terminal flower bud". If the branch blossoms once, the flower stem will dry up and retract 1 section. The flower buds placed in the axils of the lower leaves of the dried flower stems are called "axillary flower buds" or "lateral flower buds".

Leaf buds only draw long leaves, mostly in the axils of the lower leaves of the flower buds, but also at the top of the branches, which are thinner than the flower buds and develop into branches after germination.

The latent bud is born in the lowest part of the new branch and is small in shape. It does not germinate at ordinary times, but can only germinate after the flower bud, leaf bud or branch is injured. Its life span is longer and can last as long as 10-15 years.

Buds born at the root neck are called "adventitious buds". After unearthed, it is produced as a sprouting branch, commonly known as "soil bud". The germination ability of adventitious buds is very strong, and it is the main source of scion, renewal of old branches and addition of new branches. Adventitious buds did not bloom in the same year, and those with prosperous growth could develop and differentiate into flower buds at the top of the year, and bloom the following year.

According to the law of activity, the change of peony cycle can be divided into two different periods, namely, growth and development period (including reproduction) and relative dormancy period. The growth and development period is from the sprouting of scale buds in February to the withered leaves at the end of October, and the relative dormancy period from withered leaves to spring buds.

3 dormant pruning of peony

Some data think that peony pruning is mainly carried out in the growth and development period when peony begins to sprout in spring, but through the biological characteristics of peony, the author finds that peony pruning should focus on the dormancy period after defoliation in autumn. The purpose of plant health and nutrient concentration can be achieved by thinning buds and removing soil buds once in spring.

3.1 the significance of pruning

The most important thing to watch the peony is to highlight the ornamental characteristics of the peony and make the flowers big and colorful as far as possible. However, the nutrition that a tree peony can provide is limited, and the growth of tillers in the new year will consume a lot of plant nutrients, resulting in a lack of nutrition supply of old branches and retraction, but also affect ventilation, light transmission, flowering and so on. Removing the withered branches and leaves of last year can reduce the loss of plant nutrients, ensure perfect plant type and exuberant growth, improve ventilation conditions and prevent the occurrence of diseases and insect pests.

3.2 pruning method

Before pruning, the branch type and growth state of tree peony were observed, and the position and type of pruned branches were roughly determined.

Peony has the habit of withered shoots and branches, as the saying goes: "Peony grows one foot and retreats eight inches." that is to say, because there is no Lignification in the axils of the upper leaves of the branches that year, the cold resistance is poor, they die on their own when winter comes, and only half of them survive the winter. this part is the actual growth of peony branches in that year. The growth potential of branches in late October has been determined and needs targeted pruning. Remove dead branches of peony in the process of pruning, especially remove excess dead branches and excess branches (over-dense branches, parallel branches, cross branches, introverted branches, diseases and insect pests, etc.) to create good ventilation conditions to control the occurrence of diseases and insect pests. In addition, all the leaves were cut off, but the petiole of 5cm could be retained to protect the scale bud.

The flower bud differentiation of tree peony begins in the first and middle of June and ends from late September to mid-October. Pruning at this time can select the number of flower buds and branches according to ornamental needs. Ornamental peonies require strong plants and large and colorful flowers, so it is necessary to remove too many buds. If there are multiple buds on one branch, nutrients cannot be supplied centrally during flowering, which can not achieve the effect that every flower is colorful. When pruning, follow the principle of "going to the middle every three days". There are three lateral branches on the same branch. when the three lateral branches are relatively dense or cross each other, remove the middle branches. According to the difference of peony varieties, there are 1-3 flower buds on each branch. To ensure that each flower can achieve the desired ornamental effect when it becomes a flower. At the same time, all leaf buds, latent buds and adventitious buds except flower buds should be removed to ensure the nutritional supply of flower branches.

The sprouting strips of the same year can be properly selected according to the needs of plant shape. As the proverb goes, "Peony combs hair, peony washes feet", cleans up excess tillering strips, and removes all roots (flat bifurcation). So as not to waste your nutrients by pruning after sprouting in spring. Be sure to control the number of branches, while ensuring the quality of branches, can retain individual branches for renewal or correction of crown type of branches, but the rest of the branches must be cut off at the root, do not show mercy. After the preliminary pruning, check whether the shape and retention of the branches after pruning are reasonable, and ensure the bud germination and normal flowering on the selected branches, which can further improve the pruning.