Choose Healthy Bulbs
It's nearly time to add spring-blooming bulbs to the garden, so let's review the basics. A healthy bulb is solid and should feel weighty, never light, for its size. If its heft is questionable, test its firmness by gently squeezing it between your thumb and fingers. Also take care to select bulbs with no root development, mold, or blemishes, and a tunic (outer skin) that is dry and intact.
Consider Minor Bulbs
Daffodils and tulips are eye-catching, but don't overlook the smaller bulbs. These tiny gems are not only beautiful, but also hardy and tenacious. They rarely decline in vigor, and once established, many will multiply by self-sowing or producing offsets. For starters, consider Spanish bluebells (Hyacinthoides hispanica), blue squill (Scilla siberica), grape hyacinth (Muscari neglectum), Naples garlic (Allium neapolitanum), tommies (Crocus tomasinianus), and giant snowdrops (Galanthus elwesii).
Calculate Bulb Planting Depth
While it's best to follow planting instructions that come with your bulbs if they are available, here's a general rule. Most bulbs should be planted at a depth equal to three to five times their height. Sandy soils call for deeper planting, while it may be advantageous to plant more shallowly in heavy clay soils.
Adjust Drainage for Bulbs
If you're planting bulbs in an area that is typically wet or slow draining, improve conditions by adding an inch or two of course grit in the bottom of the planting hole. If the soil is usually dry, however, increase moisture retention by adding several inches of humus-rich compost below the bulb.
Bulbs look best when planted in groups or drifts, rather than straight lines or set patterns. If your adding a small sampling, say less than a dozen, an odd number of bulbs will be more pleasing to the eye. If you're planting a larger group, however, the eye cannot count the number of bulbs and you can make the drift as large as you prefer.