Bulbs in a Rock Garden

Bulbs seem like an odd fit for a rock garden if you're picturing three-foot Darwin tulips — but a whole category of smaller, daintier bulbs belongs there perfectly.

Which Bulbs Qualify

The rule of thumb is size and habit: roughly 12 to 15 inches marks the upper limit for a rock garden bulb, ruling out anything as bulky or formal-looking as hyacinths, double tulips, or most daffodils. What's left is a genuinely charming group — the smallest daffodil varieties, delicate tulip species, and the "minor bulbs" that push up almost before the earliest rock plants have opened: grape hyacinths, snowdrops, scillas, chionodoxas, and dainty wild crocuses.

A Wider Range Than True Alpines

American rock gardens have embraced bulbs more readily than the stricter alpine-gardening tradition abroad, in part because these small bulbs tolerate a much wider range of climates than true alpine plants. Native American bulb species are also gradually becoming more available, extending the rock garden's bloom season from early grape hyacinths through later scillas all the way to autumn-flowering crocuses.