One of the best sources of ethically grown native plants is the Native Plant Sale at the Harriet Irving Botanical Gardens at Acadia University in Wolfville. This year it is on Saturday June 3. I need to confirm the times, but I believe it is between 9:00AM and 1:00PM – and some of the limited stock often sells out early.
Some of the vendors and exhibitors include Baldwin Nurseries, Falmouth; LeHave Drumlins Native Plant Nursery, New Germany; Beneath the Boughs Woodland Plant Nursery, Kentville; Helping Nature Heal Restoration Gardeners, Bridgewater; the Nova Scotia Invasive Species Council and Blomidon Naturalists Society. Find out more, including a list of available plants here.