Oleander (Nerius oleander) originally comes from the countries around the Mediterranean, but has also been cultivated in our latitudes since the 19th century at the latest - although preferably in pots, because the plant is only conditionally hardy and freezes to death if there is prolonged frost or high temperatures below minus five degrees Celsius.
Usually lice are behind white spots on the oleander
Plant lice on the oleander
As beautiful as an oleander that has grown luxuriantly and is covered with delicate flowers, it has one disadvantage: the plant attracts certain diseases and pests and basically no oleander is spared a lice invasion or other injustice. A dotted white coating, mainly on the underside of the leaves, for example, is often an indication of plant lice. Scale insects in particular feel very comfortable on oleanders, but mealybugs and mealybugs can also be found occasionally. If, on the other hand, the white coating is large and can be wiped off, it is often mildew, a fungal infection that is quite easy to combat.
Common causes: Insufficient or incorrect care
Although oleander is very susceptible to scale insect infestation, you can prevent such problems with the right care and a suitable location. In particular, plants weakened by incorrect or insufficient care are attacked because they can no longer defend themselves. So take care of your oleander
- to water regularly and sufficiently
- to fertilize regularly and sufficiently
- repot once a year in fresh substrate
- cut back once a year
- to be left outside as long as possible in winter
- and get it out again as soon as possible.
- Bright and cool to winter.
- Place in a sunny and warm spot
- which, however, is at best slightly drafty.
If you follow these tips, you will strengthen your plant and make an infestation with plant lice less likely.
Fight annoying animals successfully
Once the scale insects are there, you have to fight them quickly and in a targeted manner. Otherwise, they will not only spread to the affected plant and damage it, but will also spread to neighboring plants. Combat can be done in three steps:
- Cut back badly affected shoots and leave no stubs.
- Treat the leftover parts of the plant with canola oil or soft soap
- or put a specialized means of spraying or pouring.
- Pesticides applied by watering usually have a longer-lasting effect.
- Since twice is sometimes better, you can also pour and spray.
tips
In addition to plant lice, spider mites can also be the cause of the white spots on the oleander leaves.