Horticultural Sites

Plant Identification |  General GardeningInsects & Plant DiseaseInvasives & Weeds Other Resources |  Apps

Plant Identification

Dictionary of Botanical Epithets

A useful resource for information on the meanings of plant scientific names. The epithets are largely taken from alpine plants and found in the seed lists of the North American Rock Garden Society’s seed list, alpine plant nursery catalogs and alpine references.

Flora of Virginia Project LogoVirginia Botanical Association LogoDigital Atlas of Flora of Virginia
Virginia Botanical Associates – The Flora of Virginia Project

The Digital Atlas contains the most comprehensive information available on the geographic distribution of vascular plants in the Commonwealth.

Fungi Key
Wood Decay Fungi of Living Trees

Spongipellis unicolor

Includes a Fungal Key, a Fungal Gallery,  and biological information


Great Plant Picks
Elisabeth C. Miller Botanical Garden

Includes over 800 plants zones 3 ‐ 9. Search by selectable attributes such as flower time and foliage color. Elisabeth C. Miller Botanical Garden, emphasis on Pacific Northwest. May not be 100% accurate in its findings

Key to Leaves of Virginia Trees
Virginia Tech Dendrology

Jeff Kirwan’s native tree ID online ‐ great to use with kids with wi‐fi outdoors. Get a leaf and key it via leaf shape and arrangement.

Landscape Plants
Oregon State University

Over 1,700 woody landscape plants, includes a Woody Plant Identification System, searchable by characteristics such as leaf margin, fruit shape, and flower color. Great for landscape design ideas as well as identifying existing plants.

Native Plants Database
Lady Bird Johnson Wildflower Center LogoLady Bird Johnson Wildflower Center

Explore the wealth of native plants in North America. Use search options to search for 8,811 native plants by scientific or common name or choose a particular family of plants.

Online Virtual Flora of Wisconsin
Robert W. Freckmann Herbarium

The database at Robert W. Freckmann Herbarium University of Wisconsin. Has thousands of plants listed by common name, family and genera. Each plant page has photos and information about form and habitat.

Plant Finder
Missouri Botanical Garden LogoMissouri Botanical Garden

Missouri Botanical Garden Google Mobot PlantFinder to search more than 5,400 plants by dozens of characteristics such as zone, attracts butterflies, bloom time and maintenance level. Individual plant pages include growing information, photos, noteworthy characteristics.

USDA Plants Database
United States Department of AgricultureUSDA Plants Database Logo

Authoritative source for correct plant names and US distribution maps. All plants have id and provenance. 1,000+ plants have extended information sheets.

General Gardening Sites

Advanced Master Gardeners
Virginia Cooperative Extension

Information on the 2013 Water Quality Training for MGs as well as PDF and PowerPoint files with information for Master Gardeners and the public on water quality, lawn care, turf, soils, firewise gardening and wildlife.


Healthy Virginia Lawns LogoSmart Yard Care Guide

Digital and Print Guide

Healthy Virginia Lawns

American Community Gardening Association

American Community Gardening Association Logo

“The Mission of the American Community Gardening Association is to build community by increasing and enhancing community gardening and greening across the United States and Canada.

The American Community Gardening Association (ACGA) is a bi-national nonprofit membership organization of professionals, volunteers and supporters of community greening in urban and rural communities.”

Cold Hardiness Ratings for Selected Woody Plants
United States National Arboretum

Representative plants are listed under the coldest zones in which they normally succeed

Dave's GardenDave’s Garden

Not all information is available without a membership fee. It’s overwhelmingly huge and clunky and infinitely useful. Find ratings for vendors, trade seeds, look for growing information, get advice on home improvement projects, drool over other people’s garden showcases, it’s all here. The #1 gardening site on the web, according to the Garden Writers Association.

The Garden Professors
“Advancing the science of gardening and other stuff since 2009”

Four horticulture professors, from Washington State, Minnesota, Michigan and Virginia blog about research, junk science, new plants, strange sightings and much more.

Facebook Public Group
“Welcome to the Garden Professors blog group – we look forward to your questions and comments. This group has grown out of our blog, started in 2009, addressing the science behind all things related to gardening.”

Mid-Atlantic Gardener by John Gunn

A comprehensive source of information about upcoming gardening events in the Mid-Atlantic region, and free gardening resources from regional experts for residential gardeners.

Project BudburstProject Budburst
The National Ecological Observatory Network
Citizen Science sponsored by the National Science Foundation.

Volunteers track 200+ species nation wide, recording and uploading lifecycle data. Includes lesson plans for all educational levels.    org Plants, insects, pathogens and other species that are not native to the ecosystem and cause economic , health or environmental harm.

USDA Plant Hardiness Zone Map

Type in a zip code to get your hardiness zone.

Insects & Plant Disease

Iowa State University Entomology

A knowledgebase of bugs from the United States and Canada, for identification and research. Has a “Clickable Guide” of drawings of different insect shapes, which lead to insect order pages with many photos of specimens of the different families. Has a handy page on household pests and dangerous pests. You can also submit photos for identification.

IPM for Commercial Horticulture
University of Maryland Extension

Integrated Pest Management (IPM) for Commercial Horticulture Logo

Scouts and growers contribute to weekly and bi‐weekly pdf updates on pests and pathogens for Landscape, Nursery, Greenhouse & Cut Flower industries in northern Maryland.

United States Department of Agriculture

A database of the scale insects of the world. With many photos and an identification key for 49 families of Coccoidea.

Vegetable MD Online
Cornell University

Vegetable MD Online LogoVegetable MD Online was developed to provide access to the many Vegetable Disease Fact Sheets produced over the years by Media Services at Cornell. The addition of color photographs enhances the use of these sheets for plant disease diagnosis. Has fact sheets on over  25 popular vegetables, including diagnostic keys for cucurbit and tomato. (Be sure to scroll down if it looks like there is no content.)

Invasives & Weeds

Invasive and Exotic Species of North America
University of Georgia: Invasive.org

Plants, insects, pathogens and other species that are not native to the ecosystem and cause economic , health or environmental harm.

Invasive Plant Atlas of the USA
University of Georgia

Invasive Plant Atlas of the United States Logo

The purpose of the Atlas is to assist users with identification, early detection, prevention, and management of invasive plants. The focus is on non-native invasive plant species impacting natural areas, excluding agricultural and other heavily developed and managed lands. Four main components are species information, images, distribution maps, and early detection reporting procedures.

If you know the name of the invasive plant, it will be listed on this comprehensive site.

Least Wanted: Alien Plant Invaders of Natural Areas
Plant Conservation Alliance

Illustrated, easy-to-read fact sheets on invasive alien plants with native ranges, plant descriptions, ecological threats, U.S. distributions & habitats, background of introductions, plant reproduction & dispersal, management approaches, alternative native plants, and other useful information.

Plant Invaders of Mid-Atlantic Natural Areas
Plant Invaders of Mid-Atlantic Natural Areas Book CoverNational Park Service: Fish and Wildlife Service

Invasive plants reproduce rapidly, spread over large areas of the landscape and have few, if any, natural controls, such as herbivores and diseases, to keep them in check. Many invasive plants share some important characteristics that allow them to grow out of control. These include: (1) spreading aggressively by runners or rhizomes; (2) producing large numbers of seeds that survive to germinate; and (3) dispersing seeds away from the parent plant through various means such as wind, water, wildlife and people.

Weed Identification Guide
Virginia Tech

These pages are intended to aide in the identification of common weeds and weed seedlings found throughout Virginia and the Southeastern U.S. Weeds are arranged by common name and it includes a grass ID section with keys

Other Resources

Arlington County Urban Agriculture

Community gardens, education, history and more

Arlington Friends of Urban Agriculture LogoArlington Friends of Urban Agriculture

Promoting sustainable food systems in Arlington through education, communication and research.

Capital Naturalist by Alonso Abugattas

A naturalist reveals some of the wonders of the natural world found right around the Washington, DC Metropolitan area using his own photography and his life-long experiences. 

Virginia Native Plant Society
Virginia Native Plant Society

The Virginia Native Plant Society (VNPS), founded in 1982 as the Virginia Wildflower Preservation Society, is a nonprofit organization of individuals who share an interest in Virginia’s native plants and habitats. The Society and its chapters seek to further the appreciation and conservation of this priceless heritage.


Plant NOVA Natives Plant App
Find the best NOVA natives! 

Plant NOVA Native Database Find the perfect Northern Virginia native for your planting needs using the Plant NOVA Natives plant app database.
Use the blue arrow to filter down the list based on plant characteristics such as height, moisture, sun/shade, and several others!  Click on a plant to learn more about it.

The database is very mobile friendly.  Navigate to the web page
and then follow the directions below for your Apple or Android device.

iOs Device: Add an icon for the current page to your Home screen. To quickly access the page from your Home screen, tap the Share button, then tap Add to Home Screen. The icon appears only on the device where you add it.

Add webpage to Android Home screen Android Device: How to pin a webapp/website to Android homescreen

  1. Hit the menu button, and add the page to your bookmarks. In Chrome, just tap on the star and follow the prompt.
  2. Open you bookmarks using the menu button, and find the new bookmark you’ve just added. Press down and hold on the bookmark until you see an action menu. Select Add to homescreen.

iTree Design
i-Tree LogoUnites States Forest Service

Educational software for calculating tree eco‐benefits to a community. Register to get access to the software tools, a 300 MB downloadable package (Windows only)