What is the cause of dark spots on hydrangea leaves

Hello! Hydrangea leaves have dark spots that may be due to the following.

1. Sun exposure.

Hydrangea is a short-day flowering plant, in the light of too strong conditions, it will hinder the normal growth of the plant, and black sunspots appear on the leaves, at this time, the hydrangea should be built to shade the hydrangea and spray water mist on the leaves.

2. Overwatering.

Hydrangea likes a humid environment, and under the condition of sufficient water, it will promote the growth of the plant, but excessive watering will damage the root system, resulting in poor circulation inside the hydrangea and causing black spots on the leaves.

3. Fertilizer damage.

During the maintenance of hydrangea, it is necessary to avoid blind fertilization, otherwise the fertilizer concentration is too large or too frequent, which will lead to fertilizer damage to the plant, thereby affecting the normal development of leaves, it is recommended to apply a thin compound fertilizer every 7-10 days.

4. Disease invasion.

Hydrangea will be infected with leaf spot disease under the condition of poor ventilation or improper maintenance, and small green spots will appear on the leaves of the plant at the beginning of the disease, and gradually become larger in the later stage, and the color will change to dark brown to black, and the whole hydrangea will die directly in severe cases.

White spots on hydrangea leaves are most likely a sign of powdery mildew. The main reasons for the occurrence of hydrangea powdery mildew are, poor environmental ventilation, hot and humid, high temperature and humidity, too frequent watering, insufficient branch space, potting soil with bacteria, etc., especially in summer, high temperature and humidity, after watering, the water is dissipated slowly, and powdery mildew will soon break out directly.

If it is planted outdoors in a well-ventilated environment, but the leaves at the bottom of the hydrangea branches and leaves grow too vigorously, it is also easy to cause the hydrangea to breed powdery mildew.

The specific manifestations of powdery mildew are: yellow-white spots appear on the leaves first, and then white powder appears on these spots, and under suitable conditions, the powdery mildew spreads rapidly, and the whole leaf is covered with powdery powder, which seriously affects the photosynthesis of hydrangea.

After the appearance of hydrangea powdery mildew, the prevention and control method is not difficult, powdery mildew is a fungal disease, you can use thousands of seasons of good leisure, a capsule mixed with 500ml of water to dilute, aimed at the stem and leaf spray, the leaves will be dripping as appropriate, spray once every 5-7 days, spray three times in a row, the effect is better. In the process of daily maintenance, it can also be sprayed every 25-30 days for disease prevention.

<> blackening of hydrangea leaves may be due to the excessive amount of water provided to the plant during maintenance, resulting in water decay of the plant, or it may be that too much nutrients are provided to the plant during maintenance, resulting in burns of the plant, or it may be that the soil in which the hydrangea is planted is not suitable for the growth of the plant, resulting in poor plant growth and blackening of the leaves.

1. Overwatering.

The blackening of hydrangea leaves may be due to excessive watering of the plant during the maintenance of hydrangea, resulting in water accumulation at the root of the plant, so it is necessary to provide an appropriate amount of water for the plant when maintaining the hydrangea in the later stage, soak all the soil, and provide a more humid growth environment for the plant to make it grow better.

2. Excessive fertilization.

The blackening of hydrangea leaves may also be due to the excessive nutrients provided to the plant during the maintenance of hydrangea, resulting in fertilizer damage to the plant and the inability to grow normally, so it is necessary to provide nutrients for the plant reasonably when maintaining the hydrangea in the later stage, and it is best to provide fertilizer and water to the plant after mixing it evenly, so that the plant can absorb enough nutrients.

3. Insufficient light.

The blackening of hydrangea leaves may also be due to the lack of light received by the plant in the process of growth, resulting in poor plant growth, so it is necessary to provide suitable light for the plant when maintaining the hydrangea in the later stage, so that the plant can carry out photosynthesis normally, and it is necessary to pay attention to the light intensity when providing light for the plant, so as not to burn the plant by strong light.

4. Soil discomfort.

The soil discomfort provided for the plant when planting hydrangea will also cause the leaves of the plant to turn black, so it is necessary to replace the soil for the plant when maintaining the hydrangea in the later stage, and it is best to provide the plant with sandy loam soil with rich organic matter content and good drainage, and the soil needs to be renovated before planting to improve the air permeability of the soil.