Reasons and Treatment for the Mass Appearance of Yellow Leaves on Spring Chinese Rose
A bit of knowledge to share with you about why Chinese roses develop a lot of yellow leaves in spring and how to deal with it. Keep reading!
Many flower enthusiasts have consulted about the issue of yellow leaves on Chinese roses in the past few days. Let's talk about why Chinese roses are prone to yellow leaves recently, and what other issues we need to pay attention to besides yellow leaves.
I. Reasons and Treatment for the Mass Appearance of Yellow Leaves on Spring Chinese Rose
During this period, Chinese roses have all grown flower buds. Flower enthusiasts are very happy to see flower buds on full branches. However, along with the flower buds, there are yellow leaves, even a large number of yellow leaves, which make many flower enthusiasts nervous.
Actually, when Chinese roses grow to the stage of flowering and have a lot of yellow leaves, the first thing we should rule out is the problem of maintenance that causes yellow leaves.
For example, excessive fertilization can cause damage from fertilizer, or excessive pesticide concentration can burn the leaves. However, this type of yellow leaves usually shows yellowing and burning at the leaf tip or the edge of the leaf. If the yellow leaves of our Chinese roses are abundant and show whole-leaf yellowing near the bottom of the branch, it is mostly physiological yellowing.
Physiological yellowing is a natural metabolic phenomenon of Chinese roses, often caused by the old leaves that have been growing for a long time, for example, the leaves that have already germinated in winter or the earliest leaves in early spring. By the stage of growing flower buds, these old leaves have completed their mission and will turn yellow and fall off.
There is also a situation where some originally weak old branches were not pruned in winter. When Chinese roses produce a large number of new buds in spring, these new buds on the weak branches are shaded by strong new branches, lack sunlight for a long time, and cannot get nutrients, resulting in a large number of yellow leaves.
This situation is most common in climbing Chinese roses. Sometimes even if it is not the bud on the weak old branch, as long as it is in the plant interior or bottom, it may turn yellow and fall off提前. For these naturally metabolized yellow leaves, it is recommended to remove them directly.
II. Preventing Black Spot and Red Spider Techniques in Advance
Besides yellow leaves, black spot and red spider are also on the offensive, wanting to keep our Chinese roses relatively healthy and reduce the probability of infection with black spot and red spider, it is recommended that you do the following four actions now.
1. -- Remove Blind Branches from the Plant Interior --
It is very normal for Chinese roses to grow blind branches. Many flower enthusiasts always wonder why blind branches grow. It could be due to insufficient fertilizer and water or insufficient sunlight, which may cause blind branches in Chinese roses. Therefore, when pruning in winter, you should calculate the bud points and deal with some weak buds in early spring in advance. For the specific management in early spring, you can refer to the book "How to Raise Chinese Roses from Scratch."
Although removing buds in early spring can reduce the appearance of many blind branches, you will still find that there may be some short or blind branches inside and at the bottom of the Chinese rose plant as new buds grow.
So, when you find that a pot of Chinese roses has very lush branches, you need to carefully check the inside of the plant and try to remove the short and blind branches to increase ventilation, which can greatly reduce the risk of Chinese roses being infected with diseases and pests.
However, not all blind branches need to be removed. It also needs to be combined with the seedling condition. I will explain the handling methods for different seedling conditions another day.
2. -- Increase the Spacing Between Chinese Rose Pots --
Removing the short and blind branches from the inside of the Chinese rose plant is to increase the ventilation inside the plant to reduce the infection rate of yellow leaves and diseases and pests. In addition to the ventilation of the Chinese roses themselves, environmental ventilation is also very important.
Many flower enthusiasts think that outdoor breeding has good ventilation, but that's not the case. Even if it is outdoor breeding, if the distance between the pots of Chinese roses is too close, it will affect each other's ventilation and also affect sunlight.
In the case of space permitting, it is recommended to keep a distance of about 50cm between the branches of two pots of Chinese roses, at least to ensure that the branches do not touch each other.
3. -- Isolate Weak Pots for Placement --
Common diseases and pests of Chinese roses, such as black spot, powdery mildew, and red spider, are infectious, and Chinese roses that are weak in growth are more likely to be infected. Therefore, it is recommended to place all weak pots in one area, separate from strong Chinese roses, and set up an isolation area to prevent cross-infection.
4. -- Regular Drug Prevention --
Physical prevention is just one method of preventing Chinese rose diseases and pests. Combining physical prevention with chemical control will have a more ideal effect. For example, regularly applying white pesticide on the pot soil to prevent pest damage, or regularly spraying fungicides and insecticides can effectively prevent common diseases and pests such as black spot and red spider in Chinese roses.
The above is the detailed content of the reasons and treatment for the mass appearance of yellow leaves on spring Chinese roses and the advance prevention techniques for black spot and red spider. If it can be of help to you, remember to visit the website often!