Valerian: Detect and combat diseases and pests


Valerian is naturally a very robust plant that cannot harm anything so quickly. However, if nursing mistakes creep in, some diseases and pests spread.

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Valerian (Valeriana) is considered a very robust plant and is relatively rarely infected by diseases and pests. If the location requirements are not considered, the plant can be damaged, which is reflected in growth disorders or flowering laziness.

Aphid infestation can sometimes be observed on the valerian. Powdery mildew also occurs.

Aphids - easy to spot, easy to control

Aphids are among the most common plant pests in our latitudes. There is only a limited danger to the plant. If the infestation is recognized in good time and fought accordingly, the plants generally take no damage.


If you regularly check your plants, you will not be hidden from aphid infestation. The green, brown or black pests can be seen on the plants with the naked eye. Aphids prefer to stay on the leaves and shoots of the valerian. In addition to the pests themselves, the attentive hobby gardener will also notice a sticky covering that stretches over the infected plant parts. These are so-called honeydew, the excretions of the plant pests.


Aphids can be easily controlled without the use of chemicals. If only a few pests can be identified, it is usually sufficient to strip the aphids one by one from the leaves. Nature often helps itself with plants in the field. In the ladybird, the aphid has a feared predator. If ladybugs are placed directly on the plants, the work for the hobby gardener is usually already done.

Treatment with soapy water

A shower with soapy water is an effective remedy for aphids. For this, water is mixed with soft soap. So that the plant is not damaged as a result, synthetic soap products should be avoided. About a tablespoon of soft soap is added to one liter of water.

" Tip: The effectiveness of the agent can be intensified by adding a little alcohol.

The solution prepared is filled into a spray bottle and applied over a large area. A film forms on the entire plant. This prevents the pests from breathing and lets them die. For safety reasons, the treatment can be carried out several times.

Control aphids with nettles

Nettles are much more than weeds, they can be used very well for pest control. A brew is made from the nettle leaves. Ten parts of water and one part of nettle leaves are used for this. The brew should brew for a few days before it can also be used as an effective spray.

" Tip: The plant should not be exposed to direct sunlight during the treatment with nettle stock. This would result in the formation of brown spots on the valerian leaves and flowers.

Powdery mildew - the stubborn fungal disease

Powdery mildew is rare in valerian. The emergence is favored if the plants interfere with each other's growth due to too dense standing or if there is an excess supply of nutrients.


Powdery mildew is particularly common in late summer on the valerian plant. If the days are warm and dry and the nights are already damp and cool, the ideal breeding ground for this “good weather mushroom” is created. Powdery mildew can be recognized by the white-gray and flour-like deposits on the leaves.


The easiest way is to prevent the fungus. If warm and dry late summer days are coming, hobby gardeners should use a garden hose or plant sprayer and spray the valerian plant thoroughly. Powdery mildew only occurs on dry leaves.

Milk for powdery mildew

A mixture of water and milk can become a secret weapon against mildew. For this purpose, eight parts of water and one part of milk are mixed and poured into a spray bottle. The plants are now sprayed thoroughly with it. The solution should remain on the plant for about an hour.

" Tip: So that the milk liquor cannot penetrate the soil, the root area of ​​the plant should be covered with foil.

The treatment should be done several times a week, as it can take a long time until the mildew has completely disappeared.

All infected plant parts should be cut back. Valerian tolerates this pruning and will sprout again. The entire plants should only be disposed of in particularly severe cases.

The advantages and disadvantages of natural pest control on valerian

✔ Natural pest control protects the environment and preserves the plant.
✔ No corresponding preparations need to be purchased.
✔ The ingredients are inexpensive and available in every household.

Mehrere Usually several treatments are necessary.
✖ In the case of particularly persistent infestation, it may happen that the funds are insufficient and the plant has to be disposed of.
✖ There is a certain amount of effort involved in the production of appropriate pesticides.

Avoid maintenance errors

If the care instructions for valerian are observed, the plant will thank you for its healthy growth. Ailing valerian, on the other hand, suggests various nursing mistakes: