Due to the high content of essential oils, pests such as aphids, spider mites and other vermin avoid the intensely scented lavender. For this reason, lavender can also be used as a natural remedy against such plant pests. However, weakened plants are often attacked by fungi and die.
How does lavender protect against pests?
Lavender naturally helps against pests such as aphids, spider mites and other insects, as they avoid the intensely fragrant smell of essential oils. However, weakened plants are more susceptible to fungal attack and should therefore be monitored closely.
Waterlogging causes root rot
In particular, waterlogging or generally excessive humidity - which also includes high humidity - is a big problem for lavender. Wetness causes the roots to rot and die. Paradoxically, the plant then dries up because the damaged roots no longer allow enough water to reach the above-ground parts of the plant. This phenomenon often occurs in relatively mild but wet winters - as well as when sufficient drainage was not provided in advance. Too frequent and/or incorrect watering also leads to root rot.
Treat fungal diseases quickly
Lavender plants that are diseased and weakened in this way are often attacked by fungi that cause the plant to die quickly. The so-called Phorma Lavandula, also known as lavender death or lavender death, is particularly feared. This fungus initially causes brown, then black spots, especially on the leaves. These should be removed as quickly as possible, only then does the plant still have a chance. Fungal diseases spread very quickly, which is why you should always keep a close eye on your lavender.
What to do if roots are rotting?
With a little luck you can still save lavender with rotting roots. The following measures are necessary:
- Dig up planted lavender with the entire root ball if possible.
- Remove the soil and check the roots.
- Cut away rotting roots with a sharp and clean cutting tool (€14.00 on Amazon).
- If possible, use a knife as scissors are too squeezing.
- The cutting surface should be set at an angle.
- Place the lavender in fresh, dry soil or in a new pot with fresh substrate.
- Water little!
Tips & Tricks
You can also use an infusion with dried lavender flowers or lavender oil to combat pests such as aphids on other plants. Let about one or two handfuls of flowers steep in a liter of boiled water - if possible for several hours - and spray the affected plants with the cooled lavender water.
