about paeoniarockii Growth and development characteristics

 (1) Long life span paeoniarockii is a long-lived tree species. In its life process, from seed germination to gradual aging, it undergoes a series of staged age changes. In the first three years, the seedlings grow slowly, mainly root growth, and the height of the aboveground part is less than 15 cm. After the fourth year, the growth accelerates, and the plant height can reach 40-60 cm in the fifth year. Some individuals begin to bloom after 4 years. The adult stage is strong and blooms luxuriantly, which is the best viewing period. This stage lasts about 60-100 years or longer depending on management conditions, and then enters the old age stage, the growth declines, and needs to be renewed and rejuvenated.

In the annual cycle, the paeoniarockii also shows the characteristics of spring branching, summer nap, autumn rooting, and winter dormancy. Due to climatic conditions, its annual growth period is significantly shorter than that of the Central Plains peony. In Gansu, it generally sprouts from late March to early April, blooms from late April to early June, leaves wither from mid-October to early November, and then enters a dormant period.
(2) Tall plants, strong growth potential, and strong resistance
The paeoniarockii plant is tall and has strong growth potential. After the flower buds (mixed buds) on the adult plants germinate, the branches and leaves grow in coordination to ensure the normal development and flowering of the flower buds. The leaves are initially small and curled, and only unfold and rapidly increase when the flower buds enter the wind chime period, reaching the best state after the flowering ends. Before flowering, the leaves mainly grow and develop on their own, often competing with the flower buds for nutrients and growth regulators. After the flowering period, the leaves grow fully, and their photosynthetic products become the main nutrient source for various growth and development processes of the plant.
Before flowering, paeoniarockii branches are in primary growth, that is, elongation growth is the main growth, and after flowering, they are in secondary growth, that is, thickening growth and lignification are the main growth. The growth of new branches of most varieties is better than that of the Central Plains peony, reaching 40~50cm. Because the upper part of the branch without buds dies in winter, its actual length is only about 1/3 of the annual growth.

(3) Short and concentrated flowering period, low degree of variety evolution
After the flower buds sprout, it takes about 50 to 60 days from the appearance of the buds to the flowering. The early and late flowering period is closely related to the spring temperature of the year. Warm or cold spring can advance or delay the flowering period by 7 days or more. The temperature during the flowering period has a more direct impact on the length of the flowering period. High temperature weather can greatly shorten the flowering period. Since changes in altitude affect environmental factors such as temperature, light and humidity, they have a significant impact on the flowering period of peonies. Generally, the flowering period is delayed with increasing altitude. In Lanzhou, Gansu, the peak flowering period in the urban area (1550m) is at the end of April and the beginning of May, the Heping Peony Garden (1750m) in the suburbs is in mid-May, and the Gaolan Mountain (2100m) on the south side is in late May.
The Northwest peony has a short and concentrated flowering period like the Central Plains peony. The group flowering period is generally about 20 days. Its variety evolution is low, and there are few varieties, generally less than 5%.
(4) Well-developed root system
The seedlings of Paeonia purpurogena have obvious taproots, which are typical taproot systems. However, adult plants have large fleshy root systems, and the taproots are no longer obvious. Most of the fleshy roots are 50-80cm long, and a few can reach more than 1m. In loess mountains, they can sometimes reach several meters deep. Vegetative propagation seedlings reestablish a complete root system after 2-3 years, and there is no obvious taproot.

Cultivation and management techniques of Paeonia rockii

 This paper introduces the cultivation technology and maintenance management technology of tree peony, and probes into the promotion and development of tree peony. Chinese tree peony has a long history, has been deeply loved by the majority of working people, treepeony not only flourish in China, development, but also spread to the world.

Chinese tree peony has a long history, has been deeply loved by the majority of working people, tree peony not only flourish in China, development, but also spread to the world. Under the influence of different overseas flower appreciation consciousness and aesthetic concept, different varieties of traditional Chinese tree peony have been gradually formed. In particular, Japan and European and American countries not only introduced many excellent traditional varieties from China, but also cited many precious wild species, and as parents, bred many new varieties.

Although the tree peony is so beautiful and people like her so much, when it comes to maintaining her, some people dare not pay attention to it. The reason is that everyone thinks that although the tree peony is beautiful, it is not easy to maintain, it’s easy to raise her as long as you have some knowledge.

1 the characteristics of tree peony

Peony is a kind of cold-resistant plants, like the Sun but do not like the heat, as long as to maintain adequate sunlight and 24-25 degrees C temperature, you can maintain a strong vitality. And tree peony like sandy soil and soft soil, especially avoid sticky and hard soil, so to ensure that the soil is soft peony growth factors. At the same time, the best time to plant tree peonies is autumn, should be dry autumn weather, so peonies in this season survival rate can reach 99% , winter is 96% , spring 98% , the worst in summer about 90% .

2 cultivation and maintenance management

2.1

tree Peony is widely used in gardens because of its strong growth and easy cultivation. In order to make the flowers big and colorful and obtain good ornamental results, we should take integrated scientific cultivation and management measures according to the biological characteristics and ecological habits of peony.

2.1.1 site selection. tree Peony likes cool and fears heat. It often grows poorly in areas with an annual average of 15 ° C and above, especially in summer. The optimum temperature for growth was 12 ~ 15 °C. It is advisable to shade the area slightly, in sufficient light can also be normal growth. Sex likes high dry, bogey low wet, the planting place is suitable the terrain is high open, the drainage is good. The root is thick and long fleshy root, when it grows well, the root length can reach more than 1m, so the soil layer is deep, loose and rich sandy loam. Saline-alkali soil, clay and waterlogged depression are not suitable for planting peony, like rotation avoid replanting, peony planted places, after 2-3 years before replanting.

2.1.2 selection of seedlings. (1) the variety is correct. (2) the vigorous growth stems are stout, the buds are full and the thick roots are many. Strong seedlings have strong resistance, high survival rate and rapid growth. (3) the graft site healed well and Ramets retained more roots. (4) no diseases and insect pests.

2.1.3 planting

Planting time: tree peony planting is usually carried out at the same time as the ramets. It can be planted from late September (autumn wind) to mid October. It is not suitable to plant tree peony in spring, because the root system began to move in early spring, bud germination in early March, then shoot spread leaves, now bud flowering, consume a lot of nutrients and water.

Planting method: Dig Pit before planting, diameter 30 ~ 40 cm, depth 40 ~ 50 cm, pit distance 100 cm. When digging a pit, the topsoil is separated from the subsoil so that the topsoil can be backfilled in the lower part of the pit when planting, and mixed with decomposed compost and fertilizer such as bean cake, chicken manure and sesame paste. After the soil and fertilizer are mixed evenly, pile a”Mound” in the pit, then sprinkle a layer of inorganic topsoil on it, distribute the root system of the seedling evenly on the”Mound”, make the root system extend naturally, then fill the soil, fill to half full, for gently lifting seedlings, shaking, so that the soil and root close, with feet, pay attention to the roots and the ground level. Depending on the soil conditions, such as the soil is too dry, 1 week after watering 1 time. When the soil is dry, bury the plants in fine soil. This is beneficial to keep warm over winter and maintain soil temperature, improve survival rate.

2.1.4 conservation management

2.1.4.1 water. (1) first-time seedlings should be fully watered to ensure adequate watering, promote root and soil contact, in order to absorb water and nutrients. (2) the watering time should be regular. When it is hot, it should be done before sunrise or at night when it is cool. When it is cold, it should be done when it is warm. (3) when the spring bud sprouts, it is good for the growth and development of peony to water it once. (4) hot summer weather, more rain, peonies do not need to water, water more root injury, not flowering every year. (5) to control the autumn watering, water will cause autumn hair, and lead to next year flowering difficulties.

2.1.4.2 top dressing. Peony flower large-leaf propagation, growth and development process to consume a lot of water, in order to achieve good cultivation results, timely fertilization is very important. It is usually planted without topdressing and then fertilized 3 times a year. The first time in the spring after the soil thawing, known as”Flower Fertilizer.”. The second time after flowering, called”Bud fertilizer”. The third topdressing is called”Winter fat”.

2.1.4.3 plowing and weeding. Intertillage and weeding are usually combined. Intertillage plays an active role in improving soil aeration and regulating soil moisture. Weeds not only compete with peony for water and nutrients, but also affect ventilation and light transmission, easy to occur diseases and pests. From the spring, it is necessary to follow the”Small, clean” principle of loose soil weeding, especially in July and August, hot rain frequently, weeds breed fast, but also frequently clear.

2.1.4.4 plastic trimming. Shaping and pruning is an important technical operation in tree peony cultivation, which mainly includes drying, budding and picking buds. The aim is to keep the plant in balance, with a moderate amount of branches and an aesthetically balanced posture. To maintain the Dynamic equilibrium of the above-ground and underground parts, remove vegetations and make them ventilated and light-permeable, which is conducive to concentration of nutrients and enable vigorous growth.