Alabama
Alabama Master Gardener Program
Demonstration Vegetable Garden
Jefferson County Alabama
Master Gardeners Association of North Alabama

Alaska
SoutEast Alaska Master Gardener Association Anchorage Chapter

Arizona
Arizona Master Gardener

Arkansas
Arkansas Master Gardener

California
Master Gardeners of California
Napa County Master Gardener's Web Site.

Colorado
Colorado State University Tri River Area Master Gardener Program
Master Gardeners of Denver
Colorado State Cooperative Extension Gardening in The Rockies

Connecticut
Connecticut Master Gardeners' Association

Delaware
Delaware Master Gardener Volunteers

Florida
Florida Master Gardener Program
Hernando County Florida Master Gardeners

Georgia
Georgia Master Gardener Program

Hawaii

Idaho
Idaho Master Gardeners

Illinois
Illinois Master Gardeners
Champaign County Master Gardeners Idea Garden
Illinois Extension Offices by County

Indiana
Hamilton County Master Gardeners Exceptionally nice homepage of the Master Gardeners in Hamilton County, Indiana.
Indiana Master Gardeners
Purdue Extension Gardening Tips An online resource for gardeners of all types, tailored for Indiana gardeners
Cabell County Master Gardeners
Kanawha County Master Gardeners
Monongalia County Master Gardeners

Iowa
Iowa State Extension Master Gardener Program

Massachusetts
The Western Massachusetts Master Gardener Association provides volunteer services to the general public, including an e-mail hotline to answer your gardening questions; soil testing, and presentations to civic and gardening groups.

Michigan
Michigan State Master Gardeners

Minnesota
The Master Gardener Program in Minnesota
Men's Garden Club of Minneapolis Contains information about actvities and events, history, and more.

Mississippi
Mississippi State Extension Master Gardener Program

Missouri
Missouri Master Gardener Program
Heart of Missouri Master Gardeners Cooper County University Outreach and Extension Center
Missouri Junior Master Gardener Program

Montana
Montana State University Extension Service Master Gardener Program

Nebraska
Nebraska Master Gardener Program

Nevada
Nevada's Master Gardener Program

New Hampshire
New Hampshire Master Gardeners

New Jersey
The Master Gardeners of Rutgers Cooperative Extension of Mercer County

New Mexico
Albuquerque Master Gardener
Albuquerque Area Extension Master Gardener

New York
Tompkins County Master Garden Program

North Dakota
North Dakota Master Gardener Program

Ohio
Ohio Master Gardeners

Oregon
Oregon State University Extension Service This site provides one of the best overall botanical review sites that I have seen. Units include an introduction, plant life cycles, internal plant parts, external plant parts, plant growth & development, environmental factors affecting growth, plants in communities and plant hormones & growth regulators. There are also quizzes at the end.
Oregon State University Master Gardeners
Oregon Master Gardener

Oklahoma
Oklahoma Master Gardener Program

Pennsylvania
Master Gardeners of Berks County, PA

Rhode Island
URI Master Gardener Program

South Carolina
South Carolina Master Gardener Program

North Carolina
Provided by the North Carolina Cooperative Extension Service the Master Gardener

South Dakota
South Dakota Master Gardener Program includes Master Gardener training information and news

North Dakota
North Dakota Stated University NDSU Extension Service

Tennessee
Davidson County Master Gardeners
The Madison County Master Gardeners

Texas
Junior Master Gardeners are active in Texas.
Texas A&M Master Gardener Information Wichita County Master Gardener's Association Newsletter
The Compost Bin a monthly publication of the Travis County Master Gardener Association.
Brazoria County Texas Mastergardener' Website
Wichita County, Tx Master Gardeners Newsletter
Bexar County (San Antonio) Master Gardeners.
Brazoria County Master Gardeners.
Cameron County Master Gardeners
Dallas County Master Gardeners
Henderson County Texas Master Gardeners, this is a joint program of the Henderson County Texas Extension Service and Trinity Valley Community College of Athens, Texas.
Williamson Country Extension, Texas
Texas Master Naturalist, Galveston County Chapter
Travis County Master Gardener Association
Travis County Texas Cooperative Extension

Virginia Cooperative Extension

Washington State University Gardening In Western Washington....Gardening In Eastern Washington two sites because the two sides of the state are very different....the coastal side is milder, wetter, acidic soil and Zone 7-9, while our eastern side is colder, drier, alkaline and Zone 4-5.
Washington State University Cooperative Extension

University of Wisconsin Cooperative Extension

University of Wyoming Cooperative Extension Service

Univ. of Sask Horticulture Information Service