UNITED STATES—Crocus, daffodil, hyacinth, tulip, freesia, anemone and ranunculus will not bloom until the end of winter and early spring. They are spring bulbs or early bulbs. Crocus and daffodil, including the various narcissus, will be among the first to bloom. The others as well as a few types of iris will bloom a bit later. After they finish, summer bulbs will begin to bloom.
Although they will not bloom for a few months, spring bulbs go into the garden now while they are dormant. Visually, they are still unimpressive. They are even more uninteresting when hidden from view by interment. Their planting season appropriately begins prior to Halloween and continues as long as they remain dormant and available from nurseries.
Spring bulbs generally bloom earlier within their bloom season after early planting within their planting season. Similarly, later planting delays bloom. Therefore, periodic planting of groups of the same bulbs throughout their planting seasons prolongs their subsequent bloom season. They begin to disperse roots and grow as soon as they are in the ground.
‘Bulbs’ might actually be corms, rhizomes, tubers or tuberous roots.
However, growth through the cool and rainy weather of winter remains subdued. Foliage should remain safely below the surface of the soil until warmer weather during the end of winter or beginning of spring. Like so many other plants in the garden, bulbs rely on chill to adjust their respective schedules after dormancy, but do not want to be vulnerable to it.
Winter is so mild here though that some spring bulbs do not experience sufficient chill to perform reliably as perennials. Daffodil, for example, can naturalize where it experiences more chill. Here, it may bloom best for its first spring, with less bloom annually afterward. Extensive breeding has also compromised the reliability of many perennial spring bulbs.
Some spring bulbs are actually corms, rhizomes, tubers or tuberous roots, which function much like bulbs. All are specialized storage structures that contain all that they require to survive through dormancy and then start growth for another season. They replenish their resources through subsequent active seasons to repeat the process perhaps indefinitely.
Highlight: Spuria Iris
Bearded iris are famously diversely colorful. Not much lacks from their floral color range. Spuria iris, Iris spuria, are quite different. Their floral color ranges only from purplish blue to bright white, all with prominent yellow throats. The least rare of this rare species is the subspecies carthaliniae, almost all of which blooms white. Seed is generally true to type.
Seed might be abundant without timely deadheading. However, propagation is easier by division of the copiously branching rhizomes. Such rhizomes are fibrous and tough, with comparably tough and wiry roots. They migrate to develop broad colonies, which should appreciate thinning every few years. They rarely get too crowded to bloom nicely though.
Spuria iris blooms for almost two weeks during late spring or early summer. Two or three flowers bloom in succession on stems that are nearly as high as their deciduous foliage. Leaves are elegantly narrow and upright like those of cattail, but get only about three feet tall. Carthaliniae subspecies defoliate later than others, which defoliate through summer, then foliate for autumn.
Tony Tomeo can be contacted at tonytomeo.com.