Valerian is by nature a very robust plant that is not easily affected. However, if care mistakes creep in, some diseases and pests spread.
Valerian (Valeriana) is considered to be a very robust plant and is comparatively rarely attacked by diseases and pests. If the demands regarding the location are not considered, the plant can be damaged, which is reflected in growth disorders or flowering laziness.
An infestation by aphids can occasionally be observed on valerian. Powdery mildew also occurs.
Aphids - easy to recognize, easy to fight
Aphids are among the most common plant pests in our latitudes. There is only limited danger to the plant. If the infestation is recognized in good time and combated accordingly, the plants are usually not damaged.
Recognize:
If you check your plants regularly, an infestation with aphids will not go unnoticed. 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 valerian. In addition to the pests themselves, the attentive hobby gardener will also notice a sticky coating that stretches over the affected parts of the plant. These are so-called honeydew, the excretions of plant pests.
Fight:
Aphids can be easily combated without the use of chemicals. If only a few pests can be identified, it is usually sufficient to strip the aphids individually from the leaves. When it comes to outdoor plants, nature often takes care of itself. The aphid has a feared predator in the ladybird. If ladybugs are placed directly on the plants, the hobby gardener's work is usually already done.
Treatment with soapy water
A shower with soapy water proves to be an effective remedy against aphids. For this purpose, water is mixed with soft soap. So that the plant is not damaged, synthetic soap products should be avoided. About one tablespoon of soft soap is added to one liter of water.
»Tip: The effectiveness of the remedy can be intensified by adding a little alcohol.
The prepared solution 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. To be on the safe side, the treatment can be carried out several times.
Fighting aphids with nettles
Stinging nettles are much more than weeds, they can be used very well for pest control. A decoction is made from the nettle leaves. Ten parts of water and one part of nettle leaves are used for this. The brew should steep for a few days before it can also be used as an effective spray.
» Tip: The plant should not be exposed to direct sunlight while it is being treated with stinging nettle decoction. This would lead to the formation of brown spots on the leaves and flowers of valerian.
Powdery mildew - the stubborn fungal disease
Infestation with powdery mildew is relatively rare in valerian. The emergence is favored if the plants prevent each other from growing due to being too dense or if there is an oversupply of nutrients.
Recognize:
Powdery mildew is particularly common on the valerian plant in late summer. If the days are warm and dry and the nights are already damp and cool, this creates the ideal breeding ground for this "fair-weather fungus". Powdery mildew can be recognized by a white-grey coating on the leaves that is reminiscent of flour.
Fight:
The easiest way is to prevent the fungus. If warm and dry late summer days are announced, hobby gardeners should grab the garden hose or plant sprayer and spray the valerian plant thoroughly. Powdery mildew only occurs on dry leaves.
milk against powdery mildew
A mixture of water and milk can become your secret weapon against powdery mildew. For this purpose, eight parts water and one part milk are mixed and filled into a spray bottle. The plants are now thoroughly sprayed with it. The solution should remain on the plant for about an hour.
» Tip: To prevent the milky water from penetrating the soil, the root area of the plant should be covered with foil.
Treatment should be done several times a week, as it can take a long time for the powdery mildew to disappear completely.
All affected parts of the plant should be cut back. Valerian tolerates thisCut back and will sprout again. Only in particularly severe cases should the entire plants be disposed of.
The advantages and disadvantages of natural pest control on valerian
Advantages
✔ Natural pest control protects the environment and preserves the plant.
✔ No corresponding preparations have to be bought.✔ The ingredients are inexpensive and available in every household.
Disadvantages
✖ Several treatments are usually necessary.
✖ With a particularly stubborn infestation, it can happen that the means are not sufficient and the plant must be disposed of.
✖ There is a certain amount of effort associated with the production of appropriate pesticides.
Avoid care mistakes
If the care instructions for valerian are followed, the plant will thank you with he althy growth. Sick valerian, on the other hand, suggests various care mistakes:
- The location is too humid or too dry (depending on the valerian species).
- Too much or too little watering.
- The soil is overfertilized.
- The substrate is not permeable enough.
- Potted plants are not adequately protected in winter.