Aromatic herbs from the mint family, which includes rosemary, not only taste good to us, but also to many pests. If the rosemary leaves suddenly have small, yellow or white spots, the plant is most likely infested with so-called leafhoppers.
Dwarf cicadas are often behind it
Actually, cicadas are better known from southern countries. What is less well known, however, is that there are tiny specimens in this insect family, which includes around 45,000 different species, that grow to a maximum of two millimeters in length. There are also different species of these dwarf planthoppers, with the black spotted planthopper (Eupteryx atropunctata), the sulfur leaf planthopper (Emelyanoviana mollicula) and the Ligurian leaf planthopper (Eupteryx decemnotata) troubling rosemary in particular. The name "leaf leafhopper" comes from the diet of these pests, they mainly sit on the underside of the leaves and suck the nutritious leaf juice. In good light, the small, elongated and winged animals can also be seen. The yellow or yellow-white dots or spots on the leaves are the puncture sites.
Measures against cicada infestation
Fortunately, such a cicada infestation usually does not endanger the plant, so it is primarily an optical problem. Nevertheless, you should take appropriate measures as soon as possible, since sucking out the leaf juice weakens the plant in the long term. In addition, the animals are very mobile and can spread quickly. If you want to use your rosemary in the kitchen, it is better to stay away from chemical pesticides. Instead, you can fight the animals biologically:
- As a first measure, the affected rosemary should be transplanted.
- Carefully remove the old substrate and shake the plant thoroughly.
- Rinse off the rosemary vigorously in the shower.
- Place the plant in a new pot and in fresh soil.
- Also, put them in a new location.
- Spray the plants with a diluted vinegar solution to kill any eggs that may still be present.
tips and tricks
Leafhoppers lay their eggs in autumn, and the larvae hatch in early spring. You can protect young plants with a close-meshed insect protection net, but you should still check them regularly for insect infestation. The sooner you react, the greater the likelihood that you will get rid of the little animals again.
IJA