Content
- Overview of the diseases that occur in hydrangeas
- fungal diseases
- Wrong mildew
- Powdery mildew
- Control of mildew
- Leaf spot fungi
- control measures
- Botrytis bud rot (gray mold)
- Prevention and control
- Illnesses as a result of care mistakes or deficiency symptoms
- chlorosis
- remedy
- Tips & Tricks
Diseases are not always due to brown leaves or hydrangea flowers; also nutrient deficiency can be the cause
Overview of the diseases that occur in hydrangeas
Although the Hydrangea belongs to the robust and resistant plants, this garden beauty is not immune to disease. If the attractive hydrangea once let the flowers hang or suffer from leaf discoloration, nursing mistakes are rarely the cause. Fungi and other diseases can be very hard on the hydrangea, so action is needed quickly.
fungal diseases
In certain weather conditions mushrooms thrive excellently and can attack numerous hydrangeas and other plants within a very short time. In this case, react quickly to prevent massive damage to the hydrangea. Here are the most common fungi:
Wrong mildew
This fungus triggers the most persistent hydrangea disease. It occurs frequently in conjunction with warm and relatively dry weather conditions. The whitish gray mushroom turf is found on the underside of the leaf and is therefore often overlooked in the early stages of the disease. On the upper side of the leaf are first yellowish, later marked red spots that resemble the damage of other leaf spores. In the advanced stage, the powdery mildew can also spread to the shoots, buds and flowers. In case of heavy infestation there is a risk that the hydrangea will be completely absorbed.
Powdery mildew
This bad weather mushroom is recognizable by the floury dusty coating for the layman right away. The powdery grass of powdery mildew can be easily wiped off and only affects the top of the leaves. In the progressive stage, the leaves curl up and show necrosis. The plant begins to take care of it, in case of heavy infestation it partially dies.
Control of mildew
Mildew must be consistently combated to prevent the spread of the disease:
Leaf spot fungi
In this fungal disease, the leaves turn yellowish and there are different sized, brown spots. The discolored leaf tissue thins out and is eventually repelled by the plant. The causes of leaf stain fungi in addition to high humidity in many cases, a poor supply of nutrients.
control measures
Botrytis bud rot (gray mold)
You recognize this disease by the light gray, fluffy covering that covers the buds.Gray mold is promoted by high humidity and is produced, for example, if the hydrangea in the house is under-ventilated too rarely during wintering.
Prevention and control
Illnesses as a result of care mistakes or deficiency symptoms
Illnesses that are caused by false culture conditions are generally easy to control and the hydrangea recovers quickly.
chlorosis
In this disease, the leaves turn yellow from the top and turn brown at a later stage. If this damage occurs on the older leaves, the hydrangea lacks potassium, magnesium, nitrogen and, in rare cases, phosphorus. On the other hand, if the leaf damage is manifested on the freshly-driven leaves, the hydrangea is usually lacking in iron. More rarely, a lack of copper or zinc is responsible for the chlorosis.
Iron deficiency often occurs with excess lime in the soil. Therefore, pink or red-colored hydrangeas are more frequently affected by this disease. They rely on a soil pH of over 6 to express their flower color. In order to differentiate slightly acidic soils in the basic area often has to be limed and the hydrangea can not absorb enough iron.
remedy
Tips & Tricks
If the hydrangea grows very poorly and forms small inflorescences, it is suffering from hydrangea-virosis. Unfortunately, this disease caused by mycoplasma or virus can not be treated and even prevention is not possible. The plant must be disposed of and you must not place any other hydrangeas in the same place.