13 Recognize and combat diseases and pests on clematis

Various diseases can damage the clematis. They are usually triggered by fungi, bacteria or viruses. Sometimes a pest is responsible for the outbreak of a specific disease on the clematis.

Phoma-Which

When brown leaves show up on the vine in May or June, these are the most visible symptoms of a fungal disease commonly referred to as clematis wilt . In reality, this term hides two diseases, one of which is Phonoma wilt. When the days are warm and the rain just won’t stop, this type of wilting is to be expected. It causes the following typical leaf changes:

• small, round spots of yellow-brown colour
• first leaves close to the ground are affected
• Spots spread over the whole sheet
• the leaf eventually dies and turns brown
• Fungal pathogens spread to stems and shoots
• finally, all parts of the plant above ground die

What can I do?

First of all, it is always important to recognize this infestation at an early stage, only then can you fight it successfully. You should therefore check your clematis every 2-3 days in warm, humid weather.

• remove affected leaves
• pick up fallen leaves from the ground

These two measures alone could be enough, but keep an eye on your clematis. If the disease progresses, shorten the shoot tips or cut the clematis down to the ground. After a fertilizer application, it will usually sprout again.

Fusarium-Which

Fusarium wilt comes a little later in the year because the fungal pathogens that cause it love temperatures above 20° Celsius. It could be as early as June, with the high-bred, large-flowered hybrids primarily suffering as a result. This is how the clematis change:

• Leaves turn brown starting from the edge
• Shoot tips look withered
• Symptoms appear above the site of infestation
• Shoots and leaves look dried up
• they hang down sleep

What can I do?

With this fungal disease, fungicide sprays bring chemicals into the garden, but do not bring about any improvement. If you discovered the disease in time, the following measures could save the clematis:

• collect fallen leaves
• Cut off all shoots close to the ground
• then dispose of everything with household waste

With a bit of luck, the clematis will soon sprout healthy. But it can also be a few years before she gives the first sign of survival.

powdery mildew

In dry and hot weather, powdery mildew is on the rise. The fungal pathogens do not despise food and attack a wide variety of plants in the garden. The risk of contamination for neighboring plants is high. The diseased clematis shows a changed appearance:

• at first there are small spots on the leaves
• these grow out flat
• white-grey coating covers leaves and stems
• Finally, the flowers are also affected

What can I do?

Cut off all affected plant parts and dispose of them with household waste. Also, don’t forget to collect leaves lying around the root area. The diseased vine does not necessarily need to be treated with a chemical spray because nature has given us some alternative spray solutions.

• Water and fresh milk in a ratio of 9:1
• 1 liter of water with 1 tablespoon of baking soda and 2 dashes of dish soap
• Soapy water from 1 liter of water and 100 grams of soft soap

Repeat spraying every few days.

Wrong mildew

Downy mildew can also be observed on the clematis. When high humidity and lack of air movement come together, it finds the best conditions to spread quickly.

• the lower leaves show changes first
• gray fungal growth can be seen on the undersides
• later, light spots appear on the upper sides of the leaves

What can I do?

Here, too, remove all affected parts of the clematis plant as quickly as possible and dispose of them in the household waste. Fungicides are commercially available that can then be sprayed. If the infestation is severe, you should cut back all shoots close to the ground.

Grauschimmel

Clematis planted outdoors do not have to worry about gray mold. However, some climbing specimens grow in tubs and thus inhabit closed rooms. Little air circulation and dark days in winter are ideal conditions for the development of gray mold.

• gray mold spores visible
• first of all on dead plant parts
• Infection can spread to healthy parts

What can I do?

Immediately remove all dead plant parts and all healthy ones that also show mold spores. Regularly ventilate the room where the plant is located. Try to lower the humidity in the room and only water the clematis moderately in the future when the top layer of soil is dry.

The chemical industry offers some remedies, but horsetail broth can also stop stubborn gray mold. You can find recipes for this anywhere on the internet or in specialist literature.

burn spots

There is no real disease behind burn marks, but the appearance has changed so negatively, as if a disease had ravaged the clematis. The reason for these unsightly spots I think is the sensitivity of clematis. The following triggers are possible:

• intense sun exposure
• acute water shortage
• some pesticides
• Fertilizer solution got on the leaves
• Barbecue smoke
• cold water on sun-heated leaves

What can I do?

Leaves with burn spots can no longer be saved. Remove these to make the clematis more bearable to look at. Slightly shortened shoots also promote new growth. Now that you know the triggers, you should eliminate them as much as possible.

• set up sun protection
• if possible, move clematis to a cool place
• Water the plant generously without causing waterlogging

Viruserkrankungen

Some viral diseases can also affect the growth of a clematis. Symptoms vary depending on the type of virus.

• weak growth/growth depression
• unnatural deformations of flowers and leaves
• Mosaic spots on the leaves

What can I do?

Viral diseases cannot be fought directly. The purchased vine usually brings the infection with it, because adequate industrial hygiene was not observed during its propagation. Occasionally, pests can also trigger viral infections. Remove unsightly plant parts and provide your clematis with plant strengtheners.

Pests on Clematis

Not only diseases such as fungi and viruses can be dangerous for the clematis, pests can also quickly cause major damage, up to and including the clematis. They eat leaves, flowers and roots.

slugs

Most gardeners are afraid of slugs. These little creatures are very voracious and only spare a few types of plants. Unfortunately, the clematis is not one of them. In order to combat the slimy crawlers, one must recognize an infestation in good time. But that’s not so easy, because they prefer to be out and about at night. The damage becomes visible during the day, because the leaves are eaten, possibly also the shoots.

What can I do?

To save your clematis, you must fight the slugs as soon as you spot the animals or their feeding tracks. It is important to take the impending threat to the clematis seriously, even if the snails are currently feeding on other plants.

During the day, the slugs usually hide near the plants. Find them and collect them. You can also search after sunset armed with a flashlight. If the population of snails has gotten out of hand, you may have to fight them with other means. For example with nematodes, slug pellets or a slug fence around the clematis.

aphids

There are many species of aphids in a garden, but black bean aphids and green peach aphids are the most commonly seen on clematis. They usually come in colonies and prefer to settle on young leaves and soft shoot tips. Their legacy, a sticky honeydew, attracts ants. The clematis reacts to visitors with visible traces:

• Leaves and shoots grow stunted
• Flower buds fall off
• Complications such as sooty mold occur
• yellow-brown spots become visible on the leaves
• Leaves dry up and fall off

What can I do?

Get rid of aphids as soon as you spot them. Since they don’t like moisture, you can grab a garden hose and spray the clematis with a powerful jet of water. If necessary, repeat the process over several days. The following home remedies will also help:

• Soapy water from 1 liter of water and 100 grams of soft soap
• Spray clematis with it several times
• at intervals of a few days

Beneficial insects such as songbirds, lacewings and ladybugs also prey on aphids and can be specifically settled there. Of course, for the sake of completeness, the numerous sprays from the trade should be mentioned, which can remain on the shelves with the abundance of natural pesticides.

spider mites

Spider mites can be expected in midsummer because they like dry and warm weather. The red arachnids are difficult to see from a distance because they are small and hidden on the underside of the leaves, out of sight for us. Check carefully if you suspect it!

• Undersides and lower leaves are affected first
• Infestation keeps spreading
• Leaves turn from yellow to brown in spots
• they curl up and fall off

What can I do?

Fighting spider mites is not that easy, because they multiply quickly. If you recognize the first symptoms early and interpret them correctly, you can make an important contribution by picking off the affected leaves.

Spray the clematis wet because the mites do not like moisture. If the clematis grows in a pot, you can cover the plant with translucent film for about three days after wet spraying. If not all spider mites are destroyed, the process can be repeated.

Find out more about pesticides based on neem oil and the use of predatory mites.

flower thrips

Weakened vines, clematis roots in depleted soil and dry air attract California flower thrips. You can recognize this pest by its elongated body, about 1 to 1.5 mm long, which is yellow to brown in colour. Other identifying features are tan antennae and yellow legs with spots. The vine is rarely killed, but its appearance suffers massively.

• Flowers fall off or wither quickly
• Leaves turn color and fall off
• young leaves grow deformed

What can I do?

These pests can transmit viral diseases and should be taken very seriously. They have shown resistance to pesticides approved in Germany.

Rely on natural predators such as predatory mites and lacewings, they are available online.

weevil

When clematis grows near rhododendrons or thuja,
the likelihood of infestation with weevils increases . A weakened plant and peaty soil also attract weevils. First and foremost is the weevil. The easiest way to recognize him is by his characteristic trunk on his head. The shiny black beetle is also not to be overlooked at approx. 10 mm, but it is nocturnal. Together with its white larvae, which cavort in the earth, it causes the following damage:

• eaten roots
• Disturbed growth, so-called stunted growth
• indentations on the leaves

The water absorption is disturbed by eaten roots, as a result the entire plant gradually dries up.

What can I do?

Nematodes allow you to effectively fight this pest, both adult bugs and its caterpillars. Both eat nematodes and die from them within a few days.

In addition, strengthen your clematis with plant strengtheners and exchange peat soil so that the larvae no longer feel comfortable.

voles

Finally, the physically biggest pest, which likes the roots of the clematis so much that it leaves little of it. However, no plant can survive without its roots. How to tell if voles were at work:

• complete shoots suddenly hang limp
• the plant wilts in part or in whole
• a look at the root area provides information
• the shoots are severed from the root base
• or at least gnawed on

What can I do?

You can no longer repair eaten roots, you can only hope that a residual connection is still there and the vine can recover bit by bit. Nevertheless, you should fight voles, because they come back or continue to gnaw on other plants that you have grown fond of.

The range of recommendations in this regard is long. If necessary, provide information and decide which control method suits you best.