Scale insects are a real plague: their hard shell gives them excellent protection against contact poisons, and each female lays around 2000 eggs a year - so the animals are not only stubborn, but also spread quickly. Our tips will help you to recognize and contain a scale insect infestation.
Scale insects damage olive tree
Scale insects are very difficult to spot. Since the females in particular are immobile, they protect themselves from external influences with a hard shell. Under this shield, the animals suck off plant sap and thus valuable nutrients, and they also release a poison into the plant cycle that gradually causes the host to die. Also under the shield, the female lays up to 2000 eggs from around June, from which the larvae then hatch. In contrast to the adult scale insects, the larvae are mobile and migrate to other parts of the plant and neighboring plants. Scale insects excrete a sweet honeydew that attracts other pests, such as ants or the blackspot fungus.
How can you recognize a scale insect infestation?
Scale insects can usually only be seen when the infestation is already very advanced. The tiny animals camouflage themselves excellently with a color that matches the plant, and they can usually be found on the underside of the leaf. Check your olives (and other indoor plants) regularly for scale insect infestation. You can recognize a current infestation by these signs:
- Olive tree curls leaves
- Olive tree sheds leaves
- Leaves on the olive tree dry up
- Leaves change color / turn brown
- a whitish coating can be seen on the leaves
Control of scale insects
In most cases, only chemicals help against the stubborn scale insects. So-called lice sticks, which you stick into the plant substrate, are best suited. These contain a toxin that the plant transports with the plant sap to the lice. As a result, the animals die. You can also mix a little oil (please no rapeseed oil, olives don't tolerate it!) with water and fill it in a spray bottle. Spray the plant with this mixture and repeat the process every few days. The oil clogs the scale insects' airways and kills them. Mechanical killing is also possible: Spray the scale insects with soapy water and scrape them off with a spoon or similar. In any case, you should separate the infested olive tree, otherwise the infestation can spread to other plants.
tips and tricks
Scale insects mostly attack weakened plants that suffer from a lack of light and/or are too warm. As a preventive measure, you should keep your olive tree as sunny as possible and not too warm - especially in winter!