cut flower of the month
Zantedeschia spp. (zan-te-DES-kee-uh)
Calla and miniature calla (U.S.)
Calla inflorescences consist of funnel-shaped and recurved spathes (actually colored petal-like leaves) that surround fleshy fingerlike spikes, called spadices (singular: spadix). Stems are smooth and leafless.
Standard calla (Z. aethiopica) inflorescences vary from 5 to 10 inches in length, and stem lengths usually range from about 20 to 36 inches although they can grow as long as 48 inches. Miniature calla (New Zealand hybrids) inflorescences vary from about 3 to 5 inches, and stem lengths generally range from about 8 to 20 inches, but they can grow to 32 inches in length.
Most varieties of standard callas are classic white or ivory, but there are some bicolor varieties, including the bold green-and-white ‘Green Goddess’ and the blushing lavender/pink-and-white ‘Diva Maria’.
Miniature callas’ hues include white, lavender, purple, pink, “red,” orange, bronze, rust, yellow, “brown” (deep brownish burgundy), “black” (deep reddish purple) and bicolors. These blooms tend to color differently under various growing conditions, so think in terms of a color range when ordering.
VASE LIFEWith proper care from farm to consumer, both standard and miniature callas should last from four to eight days in customers’ homes, offices, etc.
AVAILABILITYBoth standard and miniature callas are available year-round, with peaks from spring through fall.
PREPARATIONUnpack callas immediately upon their arrival at your facility. Handle these delicate flowers carefully to avoid bruising the blooms and damaging the fleshy stems.
HYDRATION AND NUTRITIONCut at least 1 inch from the bottoms of the stems, on an angle—avoid removing all of the white stem end, if possible—and place the flowers immediately into a clean container partially filled with properly mixed flower-food solution. Callas do not benefit from the nutrient (sugar) in flower-food solutions, but they do benefit from the biocide, which controls the growth of stem-plugging microbes in the water. Leaving part of the white stem ends intact helps with water uptake and vase life while reducing the chances of stem splitting or curling (see “Care Extras”).
REFRIGERATIONPlace processed callas immediately into a floral cooler, and allow them to hydrate for at least two hours before selling or arranging them. Store white varieties at 36 F to 38 F and colored cultivars at 43 F to 46 F; lower temperatures can cause chill damage. Also, do not store these flowers longer than three days.
Callas are not ethylene sensitive, and contrary to popular belief, they do not produce significant quantities of ethylene.
Callas that are shipped dry may arrive a little limp, but they will revive after being recut and hydrated. Stems can be straightened by wrapping them (but not the blooms) loosely in newspaper and storing them upright in a tall bucket or vase.