From the garden ELLEN PEFFLEY
Branches of spring-flowering trees and shrubs may look bare but their dormant buds hold a literal floral shop of hidden blooms. Spring flowers can burst open from dormant buds when they are “forced” to bloom early. “Forcing” is the horticultural term for the strategy of accelerating bloom time of dormant buds earlier than their natural cycle of waiting for the garden’s spring season to flower.
Floral buds of spring-blooming species are initiated the previous late summer and autumn months. Buds are overwintered in a rest or dormant state and will not resume growth until internal conditions have been satisfied. Six to twelve weeks of cold temperatures are required for the internal dormancy of most species to be satisfied. Once dormancy requirements have been satisfied forcing can be accomplished by providing a warm, moist environment for the yet-to-open floral buds. In nature, buds would have bloomed much later and only when the outdoor environment has warmed in the spring.
The easiest plants to force into early blooming are Forsythia (Forsythia x intermedia), lilac (Syringa vulgaris), Spirea (Spiraea prunifolia), flowering quince (Chaenomeles speciosa), crabapple (Malus spp.), redbud (Cercis canadensis), Magnolia (Magnolia spp.), and Pussy Willow (Salix caprea).
The forcing technique is simple. Using sharp pruners cut branches 1 to 2 feet in length. Bring cuttings indoor and submerge entirely in warm water. While underwater recut ends at an angle to expose more tissue, increasing water absorption. After several hours place branches wounded ends down into fresh, warm water. Warm water moves more quickly into tissues than cold water, enhancing water imbibition. Floral preservatives can be added to minimize bacterial contamination, but contamination can be controlled with frequent changes of the water.
Buds will need a few weeks to open after they have been forced indoors. Buds will swell and show color before opening into bloom. If, after several weeks buds on branches have not bloomed, it is possible that forcing was attempted too early before buds had sufficient cold exposure. Wait a few weeks and repeat with fresh plant material. For continuous displays of blooms, take cuttings every few weeks.
Plant material commonly grown in WestTexas with the earliest times for forcing: Late January/early February Flowering Quince (Chaenomeles speciosa) Forsythia (Forsythia) Mid- to late February Crabapple (Malus spp.) Redbud (Cercis canadensis) Lilac (Syringa vulgaris) Magnolia (Magnolia spp.) Pussy Willow (Salix caprea)
Ellen Peffley Harp, a retired professor of horticulture at Texas Tech University, writes about gardening for several Texas newspapers.
