National Botanic Gardens, Glasnevin

Ilnacullin (Garinish Island) Garden, Glengariff, Co Cork
An Italian Arts and Crafts garden designed by Harold Peto, on a 37 acre island in Bantry Bay

Kilmacurragh Gardens,
part of the National Botanic Gardens

Kylemore Abbey Victorian Walled Garden
Connemara, Co Galway

Trinity College Botanic Garden
Dublin

Wildflowers of Ireland
an excellent site created and curated by Zoe Williams, mentor for the ISBA World Day of Botanical Art project

Irish Wild Flowers
another excellent identification website, similar to Wildflowers of Ireland