It's about to enter the annual rainy season, and the weather is getting hotter and hotter compared to some time ago. In the summer when the rain is heavy and the rain is strong, for people, it is cool for a while, and then the high temperature mode begins. Such a cold and a hot is not only unbearable for people, but also plants will be infected with various diseases. There's no teacher calling and saying,
Boxwood macrophyllum has symptoms of graying and withering of the leaves
Friends who have planted large-leaved boxwood may know that every rainy season, if the management of seedlings is not strengthened, there will be a large-scale death phenomenon, which will eventually lead to replanting and even irreparable economic losses. We know that the large-leaved boxwood not only likes light but also tolerates shade, and the requirements for the soil are not high (drought tolerance is barren), but it is afraid of standing water, and it also grows quickly and is resistant to pruning. It has a much higher chance of disease than seedlings like Red Leaf Heather and Kanemori Privet, and once it occurs, it basically dies on a large scale. So what is the cause of the large-leaf boxwood leaves graying and withering, and what are the specific solutions?
Large-leaved boxwood stem infection bacteria appear to die in large areas
<h1 class="pgc-h-arrow-right" data-track="22" >, the reasons for the graying of the leaves of the large-leaf boxwood and the large-scale death of the large area:</h1>
1. The planting spacing of the plants is too dense, the airtight is not airtight, and the lighting is poor.
There may be some novice friends who feel that the planting is not dense enough when planting large-leaved boxwood hedges, and then the leaves are relatively sparse, have gaps, and are not beautiful. However, after a few months of raising, it is not known that the leaves are also quietly changing, and the previously dense places have suddenly become dense. Then the dense leaves could not be trimmed in time. Resulting in many leaves densely clustered, encountering the rainy season, in this impermeable condition, it is easy to breed germs, resulting in graying and withering of leaves, large areas of death; if it leads to poor lighting, it will be unfavorable to the growth and development of the later stage.
Large-scale shoot-off of the large-leaf boxwood rod diameter infection bacteria
2. The number of watering and fertilization is too much, the soil is compacted, and the soil is not cultivated in time.
Although the large-leaved boxwood is barren and has low soil requirements, we cannot grow it in an impermeable or compacted soil environment for a long time. One is not conducive to its later growth and development, the other is to affect the root respiration, if the bottom of the soil ball is slightly waterlogged, and then rotten roots, resulting in nutrients can not keep up, in the case of weak trees, it is easy to infect germs, and finally the leaves are gray and withered, and a large area of death.
3. After the rainy season, the water is not drained in time, or the root system is too much water.
When many novice friends plant large-leaved boxwood hedges, in order not to expose the soil balls, they will bury them deeply or cover the surface of the soil balls with a layer of soil to maintain their beauty. But
Large areas of dead large-leaved boxwood hedges
4. Failure to spray fungicides in time for protection.
The large-leaved boxwood hedge is sprayed with fungicides every once in a while. Because it starts in mid-May every year and lasts until the second half of September to October, during this period, the high temperature and rainy climate are frequent, the probability of leaf infection is high, and the transmission speed is extremely fast. If the fungicide cannot be sprayed in time for protection, it is easy to cause the leaves to become gray and withered, and a large area of death will occur.
The leaves of the large-leaved boxwood have just developed symptoms of graying and withering
<h1 class="pgc-h-arrow-right" data-track="12" >2, the solution of large-leaf boxwood leaves becoming gray and large-scale withering:</h1>
1. Strengthen the maintenance and management of water and fertilizer, cultivate and loosen the soil in time to improve the permeability of the soil.
Usually, in addition to nitrogen fertilizer during the growth period, occasionally we also apply some phosphorus and potassium fertilizer to the large-leaf boxwood to maintain resistance and improve growth ability, and increase the risk resistance to disease. Every two months of watering and fertilization, according to the viscosity and permeability of the soil, it is necessary to observe whether to loosen the soil once, so as to ensure the permeability of the soil.
2. Drainage work is carried out in time after the rainy season, and check whether the root system is waterlogged.
Continuous rain or high temperature exposure on sunny days after rain is extremely detrimental to the growth of large-leaved boxwood. Because after experiencing rainy days, the root breathing of boxwood will become weaker, if there is water, it is necessary to sterilize in time, put it in a cool place to dry and replant, if possible, it is recommended to mix the soil with a layer of coarse sand before planting.
Replant large-leaf boxwood hedges using coarse sand on the soil
3. Enhance the ventilation and light transmission of the whole plant of large-leaf boxwood, so as to achieve timely pruning.
The ability of the large-leaved boxwood to prune is very strong, so we can be completely assured that it will happen after pruning that it is bare and does not grow leaves. The purpose of pruning is mainly two, one is to enhance the permeability of the whole plant, and the other is to reduce the excessive consumption of nutrients due to the presence of old leaves, diseased leaves and yellow leaves. By pruning the new leaves and old sick yellow leaves with poor growth potential, it is possible to ensure that the sunlight is evenly scattered on each leaf, thereby ensuring the ventilation of the whole plant, so that the frequency of pathogen breeding can be greatly reduced.
Prune the large-leaved boxwood
4. Spray sterilization protection agents in time, so that prevention is the mainstay and treatment is supplemented.
Considering that once the large-leaved boxwood produces pathogens, its transmission capacity and speed are quite fast, so we must focus on prevention, if it is really found late, we need to cut off these infected stems and leaves in time and burn them to clean up, so as to avoid secondary transmission. The whole plant is then re-sterilized and replanted (the risk is greater, and the higher the cost is suitable for the case of small damage to the whole plant).
Large-leaved boxwood hedges that grow normally in the sun
Summary: Once the leaves of the large-leaved boxwood are grayed and withered, and a large area of death occurs, we first check whether the root system is waterlogged in time, and then observe the degree of infection of the stems and leaves, if the infection is relatively mild, we directly cut off the branches and leaves of the infected part, and then disinfect the whole plant and replant; if the infection is more serious, it is recommended to directly remove and destroy. Usually in the daily maintenance, we should pay attention to the timely work measures of trenching and drainage and cultivating loose soil, and timely prune the yellow leaves of blight and old disease in the growth process to ensure the ventilation and light transmission of the plant and improve the ability to resist diseases. In addition, after pruning, every 1-2 months, you can beat the sterilization protection agent at intervals, which can effectively reduce the plant from the invasion of germs. As long as the above points are done, the onset of large-leaf boxwood will be effectively prevented from occurring in a large area of death.