Pests and control methods of rhododendron

1. Red Spider

Rhododendron spider mainly occurs in the back of the leaves, when the occurrence of relatively large, the back of the leaves and tender shoots also have distribution. After red spider occurs, its leaves will appear small yellow and green scattered spots.

Control methods: create a well-ventilated environment, so that azalea robust growth, increase resistance to red spiders. If the occurrence amount is relatively large, the important area can be cut off to reduce the amount of its mouth; if the branches occur more densely, nicotinic biogenic insecticides such as abamectin can be sprayed.

2, cuckoo net bug

The cuckoo bug mainly occurs on the back of the leaf. When it occurs, some black spots and small insects with transparent wings about 2-3 mm long will be seen on the back of the leaf. Yellow and green spots will also appear on the front of the leaf, but they are smaller than those appearing when red spiders occur. It occurs from vein to leaf margin, and occurs more in the center of leaf than in the leaf margin.

Control methods: If the pests are relatively few, the diseased leaves can be removed and burned to prevent re-infection. If the occurrence is relatively large, imidacloprid can be used to prevent it.

3. Aphids

Aphids occur mainly on the back of leaves and tender tips, and there will be some green and white bugs, some with wings and some without wings, usually clustered together.

Prevention and control methods: when a small amount occurs, it can be taken under the tap and washed away; or hang some yellow sticky insect plates around the rhododendron; it can also be controlled by soaking tobacco water. If the occurrence is relatively large, imidacloprid can be used for spraying. A second dose should be given 3-7 days after the first dose to kill unhatched larvae in the eggs.