Here are some of my posts pertaining to specific garden (indoor too) insects/diseases and how to control them:
Scales:
Euonymus scale (Unaspis-euonymi)
Scale - Indoor House Plants
Oyster Scale - Lepidosaphes ulmi
Black Scale on Purple Leaf Sand Cherry
Beetles:
Scarlet Lily Beetle
Japanese Beetle - Popillia japonica
Lady Bug (Bird, Beetle)
Viburnum Beetle - Pyrrrhalta viburni
Spotted Cucumber Beetle - Diabrotica undecimpunctata howardi Barber
Aphids:
Aphids
Poplar Petiole Gall Aphid
Aphids On Meadow Rue
Caterpillar/Moths:
Gypsy Moth - Lymantria dispar dispar
Hydrangea Leaftier Moth (worm)
Iris Borer and Bacterial Soft Rot Control
Cnaemidophorus rhododactyla larvae Eating Rose Buds
Hummingbird Clearwing Moth: Hemaris thysbe
OtherInsects:
Thrips
Fungus Gnats and Springtails
Millipede in house plant soil
Red Wiggler Worms
Boxwood Psyllids
Boxwood Leaf Miner - Monarthropalpus flavus - the worm stage
Ontario Cicada - Homoptera cicadidae
Mealybugs - Planococcus citri
Boxwood Leaf Miner - Monarthropalpus flavus - the adult stage
Ants on Peony Flower Buds
The Common Slug - Deroceras reticulatum
Boxelder Bug - Boisea trivittata
Red Banded Leaf Hopper - Graphocephala coccinea
Rose Gall - Diplolepis rosae
Ants on Peony Flower Buds
The Common Slug - Deroceras reticulatum
Boxelder Bug - Boisea trivittata
Red Banded Leaf Hopper - Graphocephala coccinea
Rose Gall - Diplolepis rosae
Diseases:
Phytophthora Bleeding Canker on Birch
Euonymus Crown Gall - Agrobacterium tumefaciens
Eastern Filbert Blight: Anisogramma anomala on Corylus
Rose Rust - Phragmidium tuberculatum
Apiosporina morbosa-AKA Black Knot or Sh*t on a Stick
More to come...