Yellow leaves on roses: what to do Causes of yellow rose petals

table of contents

causes
Nutritional deficiency
Trace elements: iron and co.
Spider mite infestation
Wrong mildew
Star soot
Consider a combination of several causes
Preventive maintenance measures
Watering and fertilizing

The rose as the queen in the garden bed is not a modest plant, its maintenance requirements are high. If everything is to her satisfaction, she delivers us her most beautiful flowers in excess. However, if something does not suit her, she reacts sensitively and shows us this clearly with yellow leaves. This fact cannot be ignored for long. The possible causes for this yellowing must first be tracked down and remedied promptly.

causes

When the beautiful green gradually escapes from the leaves of the rose, its beauty disappears at the same time. Yes, even their life can be in danger. No owner wants to accept this bleak sight, let alone lose his roses. But in order for her to be helped, her suffering must first be exposed. The following polluters come into question:

Lack of nutrients
Iron deficiency
Spider mites
Wrong mildew
Star soot

Go on a search for clues

Yellow rose petals are clearly visible from a distance and for everyone. The causes, on the other hand, are not. An in-depth examination of the rose bush is required here. And of course the traces discovered have to be interpreted correctly. Knowledge of rose diseases and pests is necessary to make the "correct diagnosis". Only then can tailor-made measures be taken.

Nutritional deficiency

Roses are Heavy Eaterthat have high nutrient consumption. In doing so, they need a mix of different nutrients, each in an optimal dose. If there is a general lack of nutrients or certain substances are lacking, the rose often reacts with the yellow color of its leaves. The following substances should be available in sufficient quantities in a rose bush during the growing season:

nitrogen

It is the ultimate fuel for growth. When it is absent, the leaves turn pale and yellow. In addition, wild shoots can be observed.

phosphate

Low values cause yellow leaves, among other things, or their shedding.

potassium

This nutrient is important for the winter hardiness of the roses. A deficiency shows up with brown spots on the leaf blade.

magnesium

It is indispensable for the formation of the leaf green. If this substance is missing, the leaves first become lighter, then yellow and finally brown.

calcium

It is an important pH regulator. If the rose lacks it, chlorosis (yellowing) is common.

sulfur

This substance is important for the energy metabolism. If there is a shortage, young leaves turn light yellow.

tip: If you cannot clearly identify the lack of nutrient from the external signs, a soil analysis is helpful. As soon as you know what the rose is missing, you can supply it with the coveted substance.

Trace elements: iron and co.

The rose needs these key nutrients listed above in large quantities. It also needs trace elements such as boron, chlorine, iron, copper and manganese. A lack of iron, in particular, causes the rose petals to turn yellow. It is also this defect that causes the so-called Chlorosisfavored. This is also known as yellowing and bleaching. The formation of green chlorophyll is disturbed due to insufficient supply or it is even broken down. In addition to the lack of iron, the following factors also favor the development of chlorosis:

too calcareous soil
strong soil / substrate compaction
persistent drought or permanent wetness of the soil

Calcareous soils are not suitable for the cultivation of roses. These should definitely be improved by adding compost. The administration of commercially available iron supplements can also eliminate the deficiency in this nutrient.

tip: You can easily determine whether the soil of the rose is too calcareous by measuring the pH value. A value between 5, 5 and 7 is ideal for these crops.

Spider mite infestation

A lack of nutrients weakens the roses, making them vulnerable to pests and diseases. Spider mites, which are often up to mischief in dry and warm weather, can conquer weakened roses even faster. How to recognize a spider mite infestation:

in the early stages they are not even noticeable
in the course white, yellow or reddish dots can be seen on the leaves
these spots get bigger and keep spreading
Small crawling animals can be seen on the underside of the leaves
the webs of spider mites are more noticeable

Spider mites must be fought immediately, as they multiply very quickly and can also spread to other rose bushes or other types of plants. Spraying with soapy water has proven itself. In the greenhouse or house, predatory mites can also put an end to this pest plague.

Wrong mildew

A wrong location and / or too close planting can promote downy mildew. This fungus shows up on roses with reddish to brown spots on the upper side of the leaves and a gray-white mold on the underside.

cut away the affected areas
Dispose of with residual waste
never put on the compost heap
Treat rose with home remedies
in the advanced stage, if necessary use a fungicide

Star soot

Sooty is feared by rose owners because it is a very persistent and difficult to fight fungal disease. Most rose varieties are not resistant to it and therefore often fall victim to it. The rose petals do not just turn yellow, but are colorfully patterned from a mixture of yellow, brown and reddish tones.

Cut off infected shoots with a sharp knife
Always disinfect garden tools
Also collect leaves from the ground and dispose of them
diseased plant parts must not be composted
Fight sooty with a fungicide
if the location is moist and shady, it is better to replant rose
a sunny and well-ventilated place is ideal

So that the infestation does not occur in the following year as well, roses should be used as a preventive measure Plant strengtheners be treated. Regular injections with Nettle manure or Horsetail tea have proven themselves well. In addition, avoid nitrogen-based fertilization and be careful not to wet the leaves with water when watering the roses.

Consider a combination of several causes

Yellow leaves don't have to be the result of a single cause. It is therefore important not to stop investigating the cause as soon as a possible cause is found. Nutrient deficiencies and illnesses in particular often go hand in hand. Because if the vitality of the plant suffers due to a lack of nutrients, it is easy for pathogens and pests to deal with the rose.

If you stick to the first cause found and its elimination, this help for the roses may not be enough. The leaves stay yellow, new ones are added and the plant can even die.
Yellow leaves on roses do not give us time to calmly try rescue measures one after the other until all causes have been eliminated. It is better to look carefully from the beginning. Magnificent rose bushes have grown over the years and should not be removed within weeks or months.

Preventive maintenance measures

At the latest after the causes of the first yellow leaves have been successfully combated, the question of the future of the rose arises: How can the green of the rose petals be effectively protected? Good care is the best means of prevention here:

always provide sufficient planting distance
Avoid shady and damp locations
Roses love it sunny and airy
they should be able to dry off well after rainfall
ensure good soil conditions and optimize them continuously
Loosen up the soil again and again
analyze soil samples at regular intervals
Keep the pH value in the acidic range

Watering and fertilizing

Always a challenge

Roses require a lot of water, but careful watering is required:

pour carefully
Do not wet above-ground parts of the plant with water
do not use a hose
strong water jet washes away nutrients
use watering can instead
Water regularly with smaller amounts in summer
the need for water drops in autumn

The high demand for nutrients requires the use of a suitable fertilizer. The dosage also has to be precise, because a poor supply is just as harmful for the roses as an oversupply.