Why do the leaves of spring roses turn yellow? What is the reason for the yellowing of the leaves of spring roses?

Why do the leaves of spring roses turn yellow?

Today's focus is to introduce the knowledge of green plants and flowers about why the leaves of spring roses turn yellow, and the following editor will answer your questions in detail.

Recently, some rose enthusiasts have found that their roses, which were growing well, have changed leaves, or the new buds suddenly wilted, and even black stems appeared. What exactly caused this, and how should we deal with it? Today, I will analyze the reasons for the yellowing of the leaves and the corresponding solutions.

Why do the leaves of spring roses turn yellow?

Many friends think that roses should be growing rapidly in spring, and there should not be any yellow leaves. However, things are not absolute. In reality, it is still common for roses to have yellow leaves in spring. But yellow leaves do not necessarily mean there is a problem; they need to be treated differently.

1. -- Yellowing of Old Leaves at the Base of Branches --

Many rose enthusiasts do not shed leaves in winter and do not forcibly remove old leaves. As a result, yellow leaves will appear early in spring, which is actually a natural metabolic yellowing of leaves. Just remove them.

There is also a situation where roses have already sprouted in winter, but growth is slow due to low temperatures. When spring comes, they enter rapid growth, and the leaves at the bottom of the branches will gradually turn yellow and fall off. This is also a natural metabolic process, and these yellow leaves can be removed.

2. -- Young Leaves Turning Light Yellow --

Most of the yellowing of old leaves in spring roses falls into the above two situations. However, if the new leaves turn yellow, prompt remedial measures need to be taken.

In spring, if new tender leaves of roses turn yellow, it is likely due to the following reasons.

①. Excessive growth leading to physiological nutrient deficiency

After the temperature rises in spring, new buds of roses grow at a visible speed. If the rose seedlings do not have enough nutrient reserves in winter, it is easy to have a nutrient deficiency because the roots cannot absorb nutrients as fast as the growth speed. This also indirectly indicates that the root system of this rose is not very good, at least the new roots are few.

In this case, for mild yellowing of leaves, you can spray more foliar fertilizer to supplement nutrients through the leaves. Note that it is a foliar spray, not root irrigation, because the root absorption capacity is not enough. Spraying is the fastest way to supplement. It is recommended to spray a full-element water-soluble fertilizer every 2-3 days, and pay attention to reducing the concentration to prevent fertilizer damage.

②. Soil insects boring into the roots

There is another more severe situation where new leaves turn light yellow on individual branches or several branches, while other branches have relatively healthier new buds. If this occurs, first check the root system to see if there is any instability.

This situation is usually related to borers. The larvae of golden beetles or longicorn beetles bore into the main roots or stems, causing severe malnutrition. The image above shows the appearance after the roots are bored by insects. The larvae of golden beetles and longicorn beetles are very harmful, and you can refer to the book "How to Grow Roses from Scratch" for specific control measures.

The suggested method of treatment is to kill the insects first and then promote root growth and fertilization. Specific actions include: using phoxim or diazinon buried shallowly around the rose roots. The shallow burial is to release the pesticide effect more sustainably and is more effective in killing borers. Then, apply a rooting agent to the main stem near the soil, cover it with soil, and keep it moist. It is best to spray a multi-element trace element fertilizer on the leaves every 3 days to correct the yellowing leaves. Only when the yellow leaves turn green can they better photosynthesize and produce nutrients.

③. Root congestion/rot

There is another type of yellowing where the whole plant's new leaves have a light yellow appearance, the leaves are thin and pale green, looking unhealthy.

If this occurs, it is likely that there is a case of root congestion or rot. It may be that there was root congestion in winter that has not yet recovered, and after sprouting in spring, the roots cannot keep up with the growth, leading to overall nutrient deficiency. It could also be due to early fertilization in spring, damaging the capillary roots, or积水 causing root congestion.

The first step in this situation is to control water. If your potted roses have not been watered for several days but the soil is still relatively moist, it is recommended to immediately flush the roots with a large amount of water to wash away the积水 and update the soil environment, then strictly control water and fertilizer.

Place the potted plants in a sunny and well-ventilated area, and spray a full-element water-soluble fertilizer every 3 days. If there is rooting powder, it can be sprayed together, but do not apply fertilizer to the roots, only foliar spray, and be sure to reduce the concentration to avoid secondary damage from fertilizer burns.

The above is a detailed explanation of why the leaves of spring roses turn yellow and the reasons for the yellowing of spring rose leaves. I hope this article can help you with green plant management!