It may seem to be too early to be concerned with narcissus, daffodil and grape hyacinth, but this is when their bulbs go into the garden. Once established, these familiar examples, as well as early bearded iris, can be the most reliable for colorful bloom at about the same time early each spring. Crocus and freesia bloom just as early, but may not naturalize as reliably. Lily, tulip, hyacinth, anemone and ranunculus really prefer cooler winters to bloom reliably after their first spring, even though they are worth growing for just one season.
Bulbs, including corms, rhizomes, tubers and tuberous roots, can be found in nurseries when it is time for them to be planted. Gladiolus are not yet available only because they are summer blooming bulbs that should be planted a bit later than spring bulbs. None of the bulbs are much to look at while dormant, and are even less impressive once they get buried out of sight, but they have already stored up everything they need for the blooms that we expect from them next year. Once hidden below the surface of the soil, seemingly dormant bulbs secretly disperse their roots into the surrounding cool and moist soil to be ready to bloom as soon as weather allows.
In their first year, some bulbs can be planted in groups at different times to coincide with the expected durations of their particular bloom cycles. For example, if the flowers of a particular type of bulb can be expected to last two weeks, a second phase of the same bulbs can be planted two weeks after the first phase. As the first phase finishes bloom next spring, the second phase should begin bloom. However, phasing is only effective for the first season, since all bulbs of any particular variety will be synchronized by their second season.
Anemone, ranunculus and bearded iris each bloom synchronously, regardless of when they get planted, so are immune to phasing. Fortunately, the many varieties of bearded iris have different bloom seasons. Some bloom as early as narcissus. Mid-season varieties bloom shortly afterward, and are followed by late varieties. Some modern varieties bloom early, and then again after the late varieties!