What a fun topic!
Because I am planting a planting a new garden at a new property this spring I am placing more than my usual number of orders. So far, I have ordered from the following:
Plant Delights Nursery--alliums, geranium, heuchera, thalictrum, phlox
Perennial Pleasures Nursery--antique phlox
High Country Gardens--alliums, agastache, Callirhoe involucrata
Arrowhead Alpines--alliums, Crambe maritima, Seseli gummiferum
Romence Gardens--good prices and shipping for my location for more "common" perennials
Bluestone Perennials--best prices and shipping for the more "common" perennials
Heritage Flower Farm--lots of bare root species and fabulous antiques
Ambergate Gardens--excellent prices for bare root perennials
Nurseries Caroliniana--alliums
Evermay Nursery--alliums
Edelweiss Perennials*--alliums and double ranunculus
Digging Dog Nursery*
Annie's Annuals*
Dancing Oaks Nursery*
* the asterisk marks nurseries on the West Coast ( I am located in Chicago) that I usually do not order from due to very high shipping costs, but each had a few goodies that I couldn't live without that were unavailable elsewhere.
The bulk of my garden will be fragrant lilies (all planted last fall), unusual alliums, umbellifers and phlox, along with many kinds of filler plants.
If it were a normal year and I didn't have a new garden to plant, I would only order maybe a few very select goodies from my favorites--Plant Delights and High Country--and peruse the web for availability of unusual alliums and phlox from other sources.