Rose diseases: fighting symptoms & pest infestation

Unfortunately, the rose is often plagued by diseases and pests. We show how to recognize the symptoms of the disease and fight them with natural means.

Roses (pink) have high demands on their location and maintenance. If something doesn't fit, even the most robust rose variety can get sick. Black spots or a whitish coating on the leaves are often the first signs of a fungal disease. But some pests also take great pleasure in the queen of flowers. Aphids, cicadas and the like reproduce quickly and can sometimes cause great damage to the roses. To ensure that your rose stays healthy and can produce lots of beautiful blooms, it is important to react promptly and correctly. In this article, we will explain to you how you can recognize diseases and pests in roses and combat them successfully.

The most common rose diseases

Fungal diseases often affect roses in damp conditions. Discoloration of the leaves can in turn indicate a lack of nutrients. Using a few examples, we will explain to you how you can recognize rose diseases and combat them successfully.

Recognize and combat sooty soot in roses

If you see gray-black spots combined with yellowish discoloration on the leaves of your rose, it is probably an infection with Soot, which is also known as black spot disease. This common fungal disease occurs only in roses. The causative tube fungus Diplocarpon rosae multiplies particularly quickly in wet weather with temperatures above 15 ° C. Individual infected leaves and parts of plants should therefore be removed as quickly as possible and disposed of in the residual waste. You can treat heavily infested roses with a fungicide so that the plants do not lose all of their foliage. As Recognize and combat black soot as well as preventing this, we explain in detail in our special article.

Recognize, prevent and control powdery mildew on roses

Two different fungal diseases are colloquially referred to as powdery mildew. Powdery mildew on the rose (Podosphaera pannosa) can be recognized by its typical flour-like coating on the upper side of the leaf as well as by the shoots and buds. Downy mildew mushrooms (Peronosporales) in turn form dark purple spots and lead to rapid leaf fall. In both cases, you should react quickly to avoid further spread.

Various pesticides for the treatment of powdery mildew and downy mildew are available in specialist shops. You can also use home remedies such as milk or baking powder against powdery mildew. When purchasing new roses, the choice of variety can also make a significant contribution to the prevention of fungal diseases. We recommend that you watch out for resistant varieties in order to reduce the need for pesticides. If a rose has been recognized by the General German Rose Novelty Examination (ADR), you can assume that this rose is resistant to fungal diseases. More tips like you Identifying and combating powdery mildew on roses we have put together for you in a special article.

Detecting and combating rose rust

You can recognize the infestation with rose rust by the yellow-red spots on the upper side of the leaf. Later, yellow-orange pustules the size of a pin also appear on the underside of the leaves, which represent the spore beds of the pathogen. To avoid spreading, remove the fallen leaves from under the rose in autumn. But a sunny, airy location also helps to prevent fungal diseases. In our article on rose rust, we provide you with further measures for effective Combating rose rust before.

Recognize and fight chlorosis in roses

Chlorosis is a deficiency in the green pigment chlorophyll, which is why the leaf becomes lighter and turns yellow. The causes for this can be very diverse. Since chlorophyll is vital for the plant, you should react quickly at the first signs of chlorosis. A lack of calcium, nitrogen, magnesium, boron or iron, for example, leads to the leaves turning yellow. Finding the right cause is sometimes not easy, mainly because the deficiency is not necessarily through Fertilization can be remedied, for example, when the soil has an incorrect pH or there is a nutrient imbalance gives. However, these are rather special cases. If the leaves of your potted rose show chlorosis, adding a fertilizer will usually help to make up for the lack of nutrients. But over-fertilization can also lead to chlorosis. What you against yellow leaves as a sign of chlorosis we explain again in detail in our special article.

by the way: To prevent a deficiency due to an incorrect pH value or a nutrient imbalance in the soil, it is best to simply use a primarily organic fertilizer like ours Plantura organic rose fertilizer. This does not affect the pH value and contains all relevant nutrients in the correct proportions.

The most common rose pests

Unfortunately, roses are not immune to pests. The sucking and feeding damage of the small crawfish and their larvae can be quite a problem for the plants. In the following, we will explain how you can find the culprits and fight them successfully.

Fight rose aphids

The rose aphid (Macrosiphum rosae) is one of the most famous parasites on roses. It is about the size of the head of a pin and comes in the color variants green or yellowish red. The rose aphid preferably sits on young shoots and buds and sucks on the sugary phloem sap of the rose.

For now, you should try rinsing the rose with strong water pressure or wiping the aphids with a damp cloth. Agents based on neem oil, such as our purely herbal one, are particularly effective Plantura organic pest-free neem. More helpful tips about fighting Aphids on roses we have compiled for you in our special article.

Recognize and fight rose petal wasp

In the rose wasp (Caliora aethiops) the larvae represent the actual pests. The adults are glossy black with gray wings and reach a size of about five millimeters. The females lay their eggs on the underside of the leaf from May onwards. The larvae that hatch are green and yellow on the underside. These only superficially eat the leafy green, which is why one speaks of window corrosion. If the infestation is severe, then often only a skeleton of the leaf remains. You should remove affected shoots as soon as possible. Regular pruning in the spring helps prevent this. Biological pesticides based on neem oil can help in later stages. Our purely vegetable Plantura organic pest-free neem is a natural as well as extremely effective solution.

Recognizing and fighting the rose leafhopper

The infestation with rose leaf hoppers (Edwardsiana rosae) can be recognized by the white speckles on the upper side of the leaf. On the underside of the leaf you will then probably find tiny, light green insects that suck the sap from the leaves. But do not be alarmed if the movement of the leaf causes the small cicadas to jump. To prevent rose leafhopper infestation, you should choose a location for your rose where the Sun exposure is not too strong, and your plant needs sufficient nutrients give. More detailed information on Rose cicada can be found in our special article.

Recognize and fight rose petal wasp

The rose petal wasp (Blennocampa phyllocolpa) is easiest to recognize by the distinctive damage pattern: leaves curled downwards. The wasp itself is rather inconspicuous with a size of four millimeters. The symptoms are visible in warm regions as early as April, otherwise from May. Usually it remains with individual infected leaves and control is not necessary. However, if the infestation is severe, the plant will be disfigured and stunted growth will be visible. The larva of the rose petal wasp is located inside the roller and migrates to the ground in August, where it hibernates.

For control and as a preventive measure, we recommend that you remove the infected leaves including the caterpillar and dispose of them in the residual waste. Pesticides usually do not have a good effect because the caterpillar is well protected in the leaf roll.

Recognize and fight rose gall wasp

An infestation by the rose gall wasp (Diplolepis rosae) is easily recognizable by the very noticeable galls. The galls are usually several centimeters in size and sit at the tip of the shoot. Hair-like, green, yellow or reddish colored growths from the bile are very typical here. From the end of May such galls can appear on the roses. The plant will not suffer any significant damage from an infestation. The galls primarily look ugly and should be removed as soon as possible to prevent the pest from spreading.

Optimal fertilization is an important basis for resilient roses. In our article on the topic Rose fertilizer learn all about fertilizing roses.