Roses diseases: mildew, rose rust and star soot

Fungal diseases in the rosary

Roses diseases: mildew, rose rust and star soot: roses

roses are among the most popular garden plants, because they are available in many colors and species. Unfortunately, roses are haunted by numerous fungal diseases.

They are especially common Powdery mildew, Rose rust and blackspot affected. Then the roses are covered with a whitish, moldy mushroom coating and get gray-black or rust-red spots.

So that you enjoy your rose garden for a long time and do not have to fear a fungal infection, we will tell you how to recognize the three most common fungal diseases of roses, how to effectively treat rosary diseases and what you can preventively do.

Real rose tuber (Podosphaera pannosa)

Roses diseases: mildew, rose rust and star soot: rose

First signs of Rosentaupilzes are whitish deposits on the stalk.

An infestation with Genuine rosenta mushroom shows through a white, flour-like mushroom coating on the leaf tops, shoot tips and buds, which can be easily wiped off initially.

However, if you do not do something quickly, leaves that are very stinging will turn brown, then eventually die of dehydration. This is because the plant's fungus extracts all vital substances from the cells.

Not just roses are prone to this particularly severe and highly contagious fungal disease.

Even asters, phlox, larkspur, Indian armchair and lupins are often affected by mildew fungi as perennials. Mildew fungi always specialize only in certain plant species.

Therefore, you can also different vegetables like cucumbers, carrots and salsify or fruit trees such as strawberry, gooseberry, currant, apple and peach with a whitish-gray mushroom coating.


Powdery mildew

Roses diseases: mildew, rose rust and star soot: diseases

Powdery mildew on a sheet of rock pear (Amelanchier)

True mildew fungus kick especially in dry and warm weather with plenty of sunlight and nocturnal dew. An increased humidity additionally favors the development of the fungi.

Unlike many other harmful fungi, powdery mildew is not necessarily dependent on constant leaf moisture, such as rainy weather. That is why the powdery mildew fungus is also called fair-weather mushroom, which occurs mainly in spring and late summer.

In late autumn The inflamed mushroom forms winter fruit bodies in the form of black globules, which overwinter at shoot tips or knobs or in the fallen foliage.

As soon as the plant shoot starts in the spring, the spores of mildew spread again and infect new leaves and fruits.

Wrong mildew

Roses diseases: mildew, rose rust and star soot: mildew

Downy mildew on a cucumber (typical mosaic pattern on the leaf top)

The downy mildew spreads like spores of powdery mildew.

However, this is usually on the underside of leaves and does not like dry-warm weather at allbecause he needs a lot of moisture and a moderately warm to cool weather.

Thanks to the water film on wet leaves, the mushrooms can penetrate deep into the plants and grow inside the leaves.

From there they pass through small stomata to the underside of the leaves and become noticeable through a white-gray mushroom turf.

In addition, the leaves on the top of the leaves may turn brown, yellow or purple.

Especially radish and cabbage are attacked by downy mildew. But also spinach, cucumbers, lettuce or peas as well as vines and herbs can be affected.

Combat mildew and prevent

When infestation begins, the diseased leaves should be removed and affected shoot tips are cut back. In case of heavy infestation Unfortunately, you have to eliminate the whole plant.

However you should the Do not just give plant waste to the compost, because the spores spread through the air. It is better to burn the leaves or dispose of them in the household waste.

One can additionally admitted Fungicides from the garden shop use. Because of the limited duration of the treatment, it is advisable to repeat the treatment several times at intervals of 8 to 14 days.

Mix the sprays yourself

You can also do one Make the product yourselfbecause many of the required ingredients are already available at home. For five liters of such a spray mixture you need three bags of baking soda, 50 milliliters of rapeseed oil and a few drops of dishwashing liquid.

For example, this mixture allows you to spray your roses and perennials every two to three days to combat mildew.

Other proven remedies are milk or whey. The fresh milk must be diluted in the ratio 1: 8, the whey can be sprayed just like that.

Make broth from field horsetail

Roses diseases: mildew, rose rust and star soot: rust

Maintain your roses for healthy plant growth with natural and environmentally friendly fertilizers.

If you do not want your roses or other plants to be attacked by mildew, you can make their plants with a broth Horsetail repeatedly strengthen.

For this, 300 grams of fresh or 30 grams of dried horsetail in 10 liters of water are soaked for 24 hours. Then the whole thing is simmered for 15 minutes and mixed after cooling in the ratio 1: 5 with water.

While you are to avoid powdery mildew you should spray the plants for protection against downy mildew just pour the broth around the plants. Preventive may also be Netzschwefelpräparate.

Buy robust varieties. If you have planted delicate varieties of roses, it is advisable to plant them in nutrient-rich and moist soil.

A sunny and airy place It can also be helpful as it allows the leaves to dry quickly after a downpour and provides as little as possible an attack surface for the powdery mildew fungus.

Sternrußau (Diplocarpon rosae, also: Marssonina rosea)

Roses diseases: mildew, rose rust and star soot: rust

The most aggressive fungal disease on roses is the blackspot, the especially in years with cool, damp weather occurs. Even cold, heavy, impermeable soils with low humus content favor this fungal disease in roses.

When the fungus occurs, irregular purple-black, star-shaped leaf spots with frayed edges appear, which first show on the lower, ground-level leaves of the rose plant.

Without countermeasures, the rose petal around the spots usually yellowish or yellow-reddish discolored and soon falls off. Roses are significantly weakened by the fungal disease, because the leaves are an important prerequisite for flowering and plant growth.

Star black smoke on roses

Even at the first sign of fungal attack, you should treat your roses with a suitable fungicide and remove the affected areas on the roses.

Since the fungus can overwinter on the leaves on the ground, it is important to carefully remove all affected leaves and plant parts from the bed. Otherwise, after the winter period, a renewed risk of infection emanate from them.

The horsetail, which also helps to prevent mildew, is also suitable for the treatment of star soot. With the beginning of the Blattaustriebs this is sprayed several times every two weeks on the leaves. Also, broths of garlic or comfrey are helpful. Nitrogen over-fertilization, however, is harmful.

Rose rust (Phragmidium mucronatum)

Roses diseases: mildew, rose rust and star soot: diseases

The rose rust causes yellow-orange spots on the top of the leaves, while on the underside of the leaves, orange-colored pustules develop later in the summer, followed by brown-black pustules later in the fall.

From these spore camps first yellowish, then dark spores escape, which, carried by the wind, spread to other leaves.

Rosenrost mainly spreadsIf the rose bushes are too dense and the leaves can not dry well, the moisture accumulates on the ground (waterlogging) and the weather is cool in the summer.

Strongly diseased leaves fall prematurely as in the infection with Sternrußtau and thus weaken the plant. An infestation several years in a row can even mean the death of the plant.

Rose rust on roses fight

Affected leaves must be removed immediately, so that over the winter spores no new infection in the following year can take place. So cut off the shoots and leaves, collect them and dispose of them as household waste.

As with the blackspot or mildew applies that one make the rosary airy should and do it regularly got to. The roses should under no circumstances press each other or take the light.

Of course you can use the commercially available crop protection products. But you should stick to the principle: as much as necessary, as little as possible.

The natural home remedies mentioned for the control, such as field horsetail, fern and vermouth broth, are also suitable for getting rid of the rose rust. Fertilizing Kalibetont can also be helpful.

Fight against fungal diseases in roses

  1. In order to prevent the spread of fungal diseases, it makes sense initially to pick off sick rose petals early and destroy. In a mildew case, diseased shoot tips may need to be slightly cut back.
  2. A balanced supply of nutrients and adequate hydration during periods of drought are also important. Additionally you can repeated fungicide sprays help to prevent or at least curb a fungal attack.
  3. Is optimal a sunny, airy place in the garden with loose, humus rich soil. The roses should be planted with sufficient distance to each other, so that diseases and pests do not easily spread to neighboring plants and dry the plants quickly after a rain shower.
  4. Therefore, the hobby gardener should also avoid watering from above, as persistent leaf moisture significantly favors the occurrence of fungal diseases, especially Sternausßtau.
  5. The right one Spring pruning ensures adequate ventilation of the bed. In addition, well-groomed and pruned rose bushes look just nicer.

Gardener's tip: So that gardeners enjoy the abundance of flowering roses even without regular plant protection, the Federation of German Nurseries and Rose Breeders are testing new varieties for their resistance together with the Bundessortenamt.
The roses that have passed the Rosen-TÜV are high to very high resistant to fungal diseases and are regularly published on the websites of the ADR under

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Video Board: How To Treat Rust on Rose Leaves