Botanical Databases
These databases have accumulated a ton of useful resources. For best results, cross-check different sources and always consider their geographical bias.
An excellent resource. I like the Wetland Indicator Status element for grouping plants according to their moisture tolerance.
NC Native Plant Society RecommendationsA selection of native species of North Carolina
Missouri Botanical Garden Plant Finder
Click and change content directly from the front-end, avoiding complex backend processes. This tool allows quick updates to text, images, and elements right on the page, streamlining your workflow and maintaining control over your content.
Open Source Plant Images
Here are a few places to find examples of various plants and plantings. Assume a creative commons license for non-commercial use, unless noted as public 'domain'.
Harvard Arboretum Plant Images
A huge database sortable by plant name, season, description, etc. Non-commercial use only.US Fish and Wildlife Service Digital Media
This massive collection is trove of photos, video, documents, maps, and more; all public domain.
Other Resources
Sun, Soil, Wetland Indicator status