I'm no different, and I usually wind up making most of my plant purchases from Bluestone , which offers a large selection of popular perennials, sold in packs of young seedlings, at deep discounts. Bluestone's website is even better than its excellent print catalogue. You can search by plant name or let the site select plants based on your climate, soil type and color and height preferences. When I entered my zip code and requested a yellow summer-flowering plant to grow in normal soil in a mostly sunny location, I was rewarded with a list of more than a dozen possibilities. The shrub and bush specialist For larger, more developed plants, as well as rosebushes, shrubs and even some trees, White Flower Farm is your best bet.
Prices are on the high side but, given the quality, reasonable.
For the most part, the site replicates the company's extensive catalogue. But it also recommends plant combinations and provides links to general information. The site also excels at keeping up with what's hot in the garden by offering the latest hybrids and passing along recent pronouncements by trend-spotting experts. There are scores of online seed companies, but Johnny's Selected Seeds is the best all-around site, combining great service and selection, useful information and competitive prices. You'll find a large selection of standards such as tomatoes, cucumbers, carrots and marigolds, as well as more unusual crops like mesclun, that trendy mix of salad greens.