Japanese beetles have started to emerge. These pests are notorious for chomping through leaves, leaving behind the skeletal veins in the wreckage. Low-impact options to manage the adults would include botanically derived pyrethrin or pyola. Conventional products would include bifenthrin or carbaryl. But use caution: Insecticides shouldn’t be applied when pollinators are present. Adult Japanese beetles can live between 30 and 45 days. The best way to control these pests is to pick them off plants and drop them into a bucket of soapy water to kill them.
Tobacco/geranium budworms have made their appearance. The caterpillars feed on the flowers of petunias and geraniums. They are challenging to manage on geraniums because they drill into the flower bud and feed on the flower petals. Once in the bud, they are protected from insecticides. Hand-picking of the caterpillar is recommended.
Powdery mildew is present on peonies. Apply a broad-spectrum fungicide with the AI Chlorothalonil or foliar systemic propiconazole.
Pear rust continues to be an issue for pear trees. Fungicide treatment starts in the spring as the tree leafs out. Pear rust does not kill the tree, but the leaves could fall off early.
Preventive grub products can be applied now. Look for products that have the AI chlorantraniliprole or imidacloprid.
Dog vomit slime mold is showing up in mulched areas. This colorful organism is not a true fungi, but rather a saprophytic that feeds on decaying organic materials. It is most likely to show up during warm, wet periods, sometimes seeming to pop up out of nowhere overnight. The good news is that slime mold is harmless, and there are steps you can take to decrease it. Break it up and dry it out, then remove it from the area with a pitchfork or a strong stream of water.