Hi Rose! I hope you are well.

Thanks for reaching out to the UVM Extension Master Gardener Helpline.  

The damage to your echinacea plants is consistent with damage from the four-lined plant bug. This insect can feed on a wide variety of plants including herbs, vegetables and ornamentals. The insect has piercing, sucking mouth parts so when it feeds on the leaves it results in small almost angular spots. The spots can appear almost clear or brown but later appear more black. There can be drop out of tissue leaving holes in the leaves. The four-lined plant bug is quick and difficult to detect. Both the nymphs and adults feed on plants but there is only one generation each year. Nymphs emerge in late spring and the adults feed until early July so the damage is seen in May and June. The good news is that the damage is usually cosmetic although large numbers of the four-lined plant bug can be destructive to herbs.

 If you can tolerate the damage, the plants should recover. Usually, treatment is not necessary but row covers are commonly used to protect edible plants. Adults lay eggs on the plant stems so you should remove damaged plants in the fall to remove eggs. Transport the damaged plant material away from your landscape, bury or compost the damaged plant material. Here is a factsheet on these insect for more info: https://extension.umn.edu/yard-and-garden-insects/four-lined-plant-bugs.

We had Ann Hazelrigg take a look at the other two photos. We could not tell from the photo of the geranium what is going on there but if you'd like to bring in a specimen, we could take a closer look in the lab. If you would like to do that, please complete this form: https://www.uvm.edu/sites/default/files/Extension-Community-Horticulture/PDC_Specimen_Worksheet_fillable_form.pdf and send in to the Plant Diagnostic Lab (instructions are included on the form).

Regarding the yarrow, we noticed spittle on the plants and Ann suspected that spittle bugs might be the cause there. The nymphs of the spittle bugs start their feeding at the base of the plant and work their way up. You can remove them by hand or spray them with a blast of water to remove. Typically, the plants will rebound. Here is some additional information: https://extension.umn.edu/yard-and-garden-insects/spittlebugs and https://hort.extension.wisc.edu/articles/spittlebugs/. 

We hope this info helps.