Gardening Tips

Geranium pests and diseases

Geranium pests and diseases

Geraniums (geranium) are one of the most appreciated flowers in the world. Their striking appearance, capable of brightening up any balcony or garden, and the pleasant aroma that some of their species emit, make them one of the undisputed queens of spring.

If you want to learn how to keep your geraniums safe from the pests and diseases that can affect them, keep reading this EcologíaVerde article where we explain how to treat the geranium pests and diseases.

geranium pests

Of all the pests that plants are susceptible to suffering, in the geranium we are going to highlight the following that we will explain.

geranium butterfly

The geranium butterfly, also called as the geranium borer, is one of the most harmful pests suffered by the geranium, particularly in Spain in the area bordering the Mediterranean Sea. This pest needs maximum attention and control because it can spread easily from one plant to another, thus causing the death of several specimens drastically and in a very short time.

Luckily, it’s pretty easy to spot. You just have to watch if the stems of your geranium are pierced. If so, most likely the caterpillar is already inside. This causes internal damage to the eat the plant from the inside weakening its leaves and flowers.


Aphids measure about 3 millimeters and are placed in all tender zones of the plant. Your symptoms are rolled up sticky leaves due to the honeydew secreted by these tiny little insects. In addition, this molasses is the ideal breeding ground for the appearance of bold or the increase in transmitting viruses between different nearby individuals.

Do not hesitate to consult the following article with Home remedies to eliminate aphids in plants to have more information on the subject.

Red spider

This pest affects geraniums during the rise in temperature in the spring and summer seasons. They measure about 0.5 millimeters in size, reddish in color and are located on the underside of the leaves. It is not possible to distinguish them with the naked eye so for them you will need to use a magnifying glass.

However, the symptoms caused by this pest in geraniums are very recognizable. From the silver colour that begins to appear on the sheetsuntil the possibility of seeing small spider webs in case of severe attack.

Discover How to eliminate the red spider of the geranium in the following EcologíaVerde post that we recommend.

White fly

with no more than 3 millimeters in size, the whitefly is one of the pests that prefer the high temperatures and the excess moisture to reproduce. Luckily, it is very easy to identify since it is only necessary to shake the plant slightly to see how it creates a cloud of insects around him. It feeds on the sap so that in a short time it is capable of severely weakening it. Generally, it deposits its eggs and larvae on the underside of the leaves.

You may also be interested in this other article on the Whitefly: how to eliminate it.


Brown in color and looking pretty similar to a wartappear on stems and leaves of the geranium. Inside are the eggs and larvae of the cochineal which, once in their adult phase, have a characteristic silver colour. They adhere to the stem or leaves to feed on the plant and, in turn, excrete honeydew which, as in the case of aphids, can also end up causing the appearance of fungi.

Discover How to eliminate the cottony mealybug: treatment and home remedies in this other EcologíaVerde article that we recommend.


There are several species, in addition to the caterpillar of the geranium butterfly, capable of affecting these plants. The best way to fight them is to remove them by hand and ensure that the underside of leaves is free of eggs.

Do not hesitate to consult this post with Home remedies to eliminate caterpillars from plants, here.

green mosquito

These tiny sucking insects stick their beak in the leaves of the geranium to absorb the sap. The clearest symptoms are loss of color in the leaves or the appearance of reddish tones on the leaf before its fall.


nematodes enter the roots in order to feed on the plant. For this reason it is very difficult to realize that the plant is being attacked by them. However, some of its symptoms are easy to recognize, such as loss of color of leaves or yellowish tones in them before finally withering away.

If you want to know more about What are nematodes: characteristics, classification and examples, we recommend that you read this EcologíaVerde article.

Geranium Pests and Diseases - Geranium Pests
Geranium pests and diseases -

Geranium diseases

Once we have seen what the geranium pests are, we are going to detail the diseases that this plant can suffer.


Rust is one of the most common diseases on geranium. It is distinguished by being dark-colored pustules that become orange and are located on the underside of the sheets causing you to be wither and dry.

Find out how to combat rust, here.


This disease mainly affects the leaves and flowers, forming a dark gray mold layer that ends up causing you to be they rot quickly.

powdery mildew

This fungus is easily identified by the appearance on the upper part of the leaves of a whitish powder that over time yellow the leaves until they are completely dry.

Do not hesitate to consult the following article on How to combat powdery mildew with home remedies in EcologíaVerde.


Small brown spots that appear on the most adult parts of the plant, specifically on its leaves and that cause general weakness.


Small dark brown spots that appear on the leaves, buds and buds of the geranium and that end up expanding until wither the area affected.

If you want to know more about Anthracnose: what it is and treatment, you can do so in this post that we recommend.

foot disease

This fungus also produces stains similar to those of anthracnose Therefore, although it can be easily confused, it can also be treated using the appropriate fungicide.


These bacteria appear in the form of necrotic spots on the leaves until they dry up and fall off. there is no cure for them, so it is necessary to isolate the plant from the rest to avoid contagion.

mosaic virus

Geraniums can also be infected by plant viruses such as mosaic virus. Its most representative symptoms are the appearance of variegated and yellowish spots on the leaves and malformations in its flowers.

Geranium Pests and Diseases - Geranium Diseases
Geranium pests and diseases -

How to prevent geranium pests and diseases

Preventive treatments, as usual in this type of case, are usually always more advisable in the long run. As far as pests are concerned, it is convenient to plant in the garden or the entrances to the home such as doors and windows aromatic plants that help keep unwanted insects away, such as lavender, basil, mint, rosemary or citronella.

As for fungi and diseases, the best is:

  • Keep the yard and the aerated plant.
  • Withdraw always immediately the parts of the plants in poor condition.
  • not leave than the leaves and other fallen plant matter accumulates.

When the temperature is mild and there is rain, it is convenient apply natural fungicides like the one made from milk preventively, since they are the ideal conditions for the development of fungi.

We leave you this article on Geranium care and you are curious about caring for plants, do not hesitate to take a look at the following video on natural insecticides from EcologíaVerde that will help you keep them in perfect condition.

If you want to read more articles similar to Geranium pests and diseaseswe recommend that you enter our Garden Care category.

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