Groups

East

Lanark County
 Website
 Facebook
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Lanark County Master Gardeners (serving Almonte, Carleton Place, McDonalds Corners, Pakenham, Perth, Smiths Falls, Westport, Sharbot Lake, and Portland)

Lindsay and District
 Website
Lindsay and District Master Gardeners (serving Woodville, Cameron, Pontypool, Bethany, and Janetville)

Northumberland
 Website
 Facebook
Northumberland Master Gardeners (serving Cobourg, Port Hope, Garden Hill, Grafton, Gores Landing, Warkworth, Brighton & surrounding area)

Ottawa-Carleton
 Website
 Facebook
Master Gardeners of Ottawa-Carleton (serving Kanata, Nepean, Ottawa, Vanier, Gloucester, Goulbourn, Cumberland, West Carleton, Osgoode Ward, Rideau Ward)

Peterborough and Area
 Website
 Facebook
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Peterborough and Area Master Gardeners (serving Apsley, Bailieboro, Cavan, Hastings, Havelock, Janetville, Norwood, Indian River, Lakefield, Omemee, Selwyn, Young's Point, and Warsaw)

Prince Edward County
 Website
 Facebook
Prince Edward County Master Gardeners (serving the communities of Prince Edward County, Belleville, Trenton and Napanee and the rural areas around these centres)

1000 Islands
 Website
 Facebook
 Instagram
1000 Islands Master Gardeners (serving the geographic area of Frontenac County, including Kingston, Gananoque, Napanee, Brockville, Landsdown, Mallorytown, Rockport, Wolfe Island, Howe Island and the surrounding areas.)

North

Algoma
 Website
 Facebook
Algoma Master Gardeners (serving Sault Ste. Marie, Thessalon, Echo Bay, Richards Landing, Hilton Beach, Bruce Mines, Manitoulin Island and rural areas in between)

Georgian Bay
 Website
 Facebook
Georgian Bay Master Gardeners (serving District of Parry Sound)

Haliburton
 Website
 Facebook
Haliburton County Master Gardeners (serving Haliburton Highlands including the villages of Haliburton, Minden, Carnarvon, Wilberforce and Harcourt)

Lake Simcoe South
 Website
 Facebook
 Instagram
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Lake Simcoe South Master Gardeners (serving York Region)

Muskoka
 Website
 Facebook
Muskoka Master Gardeners (serving Muskoka and Almaguin Highlands)

North Bay
 Website
North Bay Master Gardeners (serving Callander, Powassan, Sundridge, Mattawa, Sturgeon Falls, Temagami, Temiscaming and rural areas in between)

Simcoe County
 Website
 Facebook
Simcoe County Master Gardeners (SCMG) (serving the following communities: Blue Mountain, Collingwood, Stayner, Creemore, Wasega Beach, Elmvale, Midland, Washago, Orillia, Barrie, Innisfil, Alliston, Bradford, Tottenham and all points in between)

Thunder Bay
 Website
 Facebook
Thunder Bay & District Master Gardeners (serving communities to the west, including Dryden, Fort Frances, Rainy River and Kenora, and communities to the east, including Nipigon, Geralton, Long Lac and Wawa)

South & West

Essex-Windsor
 Website
 Facebook
Essex-Windsor Master Gardeners (serving Leamington, Kingsville, Essex, Amherstburg, LaSalle, and Windsor)

Grand Erie (formerly Brantford)
 Website
 Facebook
 Instagram
Grand Erie Master Gardeners (serving Brantford, St. George, Paris, Glen Morris, Waterford, Burford, Simcoe, St. Williams, Scotland and surrounding areas)

Grey County
 Website
 Facebook
Grey County Master Gardeners (serving Owen Sound, Flesherton, Durham, Markdale, and parts of Bruce County)

Guelph-Wellington
 Website
 Facebook
Guelph-Wellington Master Gardeners (serving Guelph, Fergus, Elora, Rockwood, Mount Forest, Arthur, Erin, and the townships of Wellington County)

Halton Region
 Website
 Facebook
 Instagram
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Halton Region Master Gardeners (serving Burlington, Hamilton, Milton, and Oakville)

London Middlesex
 Website
 Facebook
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London Middlesex Master Gardeners (serving London and Middlesex County and all towns therein)

Niagara
 Website
 Facebook
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Master Gardeners of Niagara (serving St. Catherines, Welland, and Grimsby)

Stratford
 Website
Stratford Master Gardeners (serving St. Marys, Listowel, Oxford County, and most of Perth County)

Waterloo Region (formerly Kitchener)
 Website
 Facebook
 Instagram
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Waterloo Region Master Gardeners (serving Kitchener, Waterloo, Cambridge and area)