Vegetation

Use lawn only when it performs a specific function such as a play surface, pathway, or foreground for plant display, thus reducing extra inputs of chemicals, energy and time.
Turf Grass Madness: Reasons to Reduce the Lawn in Your Landscape
Groundcover Alternatives to Turf Grass
Bee Lawns: Turf Grass with Flowering Plants
South Greenhouse Garden (an example of a no-lawn garden at UDBG)

Eliminate the use of and remove vegetation that can harm ecosystems, such as recognized invasive species.
Mistaken Identity? Invasive Plants and their Native Look-Alikes
Plants for a Livable Delaware

Choose plants that are adapted to the site’s conditions and support local wildlife.
Best Plants for Delaware to Bring Birds to Garden by Doug Tallamy
Pollinator Plants Mid-Atlantic Region
Controlling Backyard Invasives

Consider replacing alien species with appropriate native species that achieve the same purpose (e.g. aesthetics, function).
Meadows & Buffers for Bees: Creating Mid-Atlantic Pollinator Habitats
Native Plants for Delaware Landscapes (trees & shrubs)
Plants for Wildlife Habitat and Conservation Landscaping (Chesapeake Bay Watershed)

Use Integrated Pest Management (IPM) strategies (i.e. scouting, life-cycle knowledge and decision-making based on that information).
Protecting Pollinators at Home: Smart Pest Management
Organic Approved Pesticides
Organic Approved Pesticides Overview
Penn State Extension Weed Identification
Univ Mass Amherst Weed Herbarium

Maintain and increase vegetative coverage to increase biodiversity.
Supporting Biodiversity in the Garden
Monarch Waystation Brochure
Monarch Waystation Program
Delaware Gardening: Challenge to Newcomers
Attract Lepidoptera to Your Garden Brochure

Preserve as many important (mature, healthy, native) plants as possible.
Checklist for Plant Removal Decisions