Native plants which evolved in a particular area provide more benefits to wildlife than non-native plants. Many insects and animals have specialized relationships with specific types of plants. Monarch butterflies' caterpillars eating only leaves from milkweed plants is one example out of thousands. By planting a diverse range of native plants, and using ecological gardening/landscaping practices, you can create Habitat in your own yard or urban environment.
Blue Stem Natives (Norwell, MA)
Native Plant Trust (Framingham, MA)
Russell's Garden Center (Wayland, MA)
The Monarch Gardener (Ipswich, MA)
Lady Fern Farm (Central MA)
City Natives - in Mattapan
Attracting Pollinators to the Garden (Ohio State University Extension)
Belmont native plant seed library at Belmont Public
Mass Audubon Sanctuaries (Throughout Massachusetts)
Ecological Landscaping Alliance (New England)
Grow Native Massachusetts is based in Waltham and has a plant sale in the spring, usually June. Their website is also full of information
Pollinator Pathways - Public and private pesticide-free corridors of native plants that provide nutrition and habitat for pollinating insects and birds. Even the smallest green spaces, like flower boxes and curb strips, can be part of a pathway.