Introduction to the Causes of Black Stem in Roses How to Deal with Black Stem in Roses?
A brief knowledge sharing with you about the introduction to the causes of black stem in roses and how to deal with it in the field of green plants and flowers. Next, the editor of this site will introduce it to everyone.
Introduction to the Causes of Black Stem in Roses How to Deal with Black Stem in Roses?
Today, following yesterday's topic, we continue to talk about the issue of black stem in roses. The common causes of black stem can be summarized into the following points, and everyone should pay attention to prevention and avoidance during the maintenance process.
Common Causes of Black Stem in Roses
Black stem in roses most easily occurs in summer and early spring, why is that? You will understand after learning the causes of black stem in roses.
1. Fertilizer Damage Causes Black Stem in Roses
Fertilizer damage is one of the most common causes of black stem in roses, and it is also the most serious type of black stem.
Black stem caused by fertilizer damage usually develops slowly, and before we realize it, the entire branch has turned black. This type of black stem starts from the bottom or middle of the rose plant and gradually spreads upwards.
This usually happens when fast-acting fertilizer is used during hot weather. Some rose varieties may enter a brief dormancy in summer, grow slowly, and easily develop black stem when too much fertilizer and water are applied.
If slow-release fertilizer is used, the fertilizer effect is concentrated in the summer, which can easily cause slow fertilizer damage, leading to black stem in roses and continuous development.
In winter, when planting bare-root seedlings or repotting, the roots of roses come into direct contact with the base fertilizer, which can easily lead to black stem in the spring. Some start from the top, and some from the bottom.
Prevention Methods
The most important thing to prevent fertilizer damage-type black spot is: ① Avoid using raw or concentrated fertilizers. ② Do not mix slow-release fertilizers with soil or use them as base fertilizers in summer. ③ When repotting or planting, the base fertilizer must not come into direct contact with the roots of the rose.
If the above three points are followed, fertilizer damage-type black stem can be avoided. Of course, high-concentration insecticides and fungicides should not be used for root watering.
2. Weak Stem Blackening
Sometimes black stem in roses is a natural choice of the rose itself. For example, a vigorous rose plant may have individual thin and weak old branches at the bottom turn black, which is the natural elimination of the rose.
Because thin and weak old branches have poor vitality and do not receive sufficient light and fertilizer at the bottom, the rose plant will choose to abandon such branches directly. Therefore, during routine pruning, it is necessary to cut off the thin and weak branches and old branches at the bottom.
3. Wound Infection
Wound infection is also an important cause of black stem in roses. For instance, pruning on rainy days can lead to infection after the cut ends are rained on, which may cause partial black stem. If not dealt with promptly, the black stem may continue to spread.
This situation often occurs in grafted roses. If the wound does not heal after grafting and is rained on or contaminated with dirty water, it may lead to black stem. Sometimes, the roses purchased by our gardening friends may also have black stem on some grafted branches, which can wither.
Prevention Methods for Wound Infection
I have written all my 10 years of rose cultivation experience in the book "How to Start Cultivating Explosive Roses from Scratch". In the book, I specifically mention that pruning should be done in the middle of a sunny day. At this time, the sunlight is strong, and the wounds dry quickly, reducing the risk of infection. Gardeners with conditions can also use wound healing agents after pruning to prevent infection.
Actually, many of the problems our gardening friends encounter are the same. For beginners, it is inevitable to encounter various problems when growing roses. At the root, it is because they have not mastered the correct cultivation methods.
I recommend you read "How to Start Cultivating Explosive Roses from Scratch", from choosing the variety and seedlings at the beginning, to step-by-step maintenance, and finally to flowering. By following the rose growth process step by step, you can successfully cultivate roses.
The above-sharing content about the causes of black stem in roses and how to deal with it is for reference by green plant enthusiasts.