CANADA

The Canadian Nursery Landscape Association (CNLA)
www.canadanursery.com

Landscape Ontario Horticultural Trades Association
www.landscapeontario.com

Calgary Horticultural Society
www.calhort.org

Environment Canada
www.ec.gc.ca

The Ontario Trillium Foundation
www.trilliumfoundation.org

Ontario Ministry of Agriculture and Food
www.gov.on.ca/omafra/english/index.html

Ontario Horticultural Association
www.gardenontario.org

Blossom Hill Nursery
www.blossomhillnursery.com

Heritage Perennials
www.perennials.com

Hortico
www.hortico.com

Ontario Tree Seed Plant
ontariosforests.mnr.gov.on.ca/otspoverview.cfm

Richters Herbs
www.richters.com

Horticultural Marketing
www.hortmark.com

UNITED STATES

Elisabeth C. Miller Library
http://depts.washington.edu/hortlib/index.shtml

Lawn & Landscape Magazine
www.lawnandlandscape.com

North Carolina State University
www.ces.ncsu.edu/depts/hort

Perennial Plant Association
www.perennialplant.org

The University of Georgia College of Agricultural and Environmental Sciences Cooperative Extension Service
http://pubs.caes.uga.edu/caespubs/horticulture/info-tip.html

University of Florida (IFAS Extension)
http://prohort.ifas.ufl.edu