138 J.E. FAUST, J.M. DOLE, AND R.G. LOPEZ
equipment performance. Plants of tropical origin typically cannot with-
stand cold temperatures, usually below 10–13◦C, and should be stored
at 13–18◦C (Wang 1987; 1994).
Chrysanthemum and carnation cuttings tolerate storage much bet-
ter than geranium, lantana, and portulaca (Portulaca oleracea) cuttings
(Altstadt and Holley 1964; Druege et al. 2000; Rapaka et al. 2007a,
2007b, 2008). Altstadt and Holley (1964) noted that carnation cuttings
could be cold stored in polyethylene-lined boxes at 0.6◦Cforupto
2 months with no apparent loss of fresh weight, branching, or cut-
flower yield. Carnation cuttings could be stored at 4◦C for 6–8 weeks
with either no effect on rooting or an increase in rooting percentage and
a decrease in rooting time (Garrido et al. 1998). Selected cultivars of
potted chrysanthemum cuttings could be stored for up to 6 weeks at
0–3◦C; however,−1or− 3 ◦C resulted in freeze damage (Rajapakse and
Kelly 1995; Rajapakse et al. 1996). However, flowers were smaller for
plants that were grown from cuttings stored for 4–6 weeks than for
plants from unstored cuttings. Other species are more strongly affected
by storage. For example, geranium cuttings stored for 5 d decreased in
performance, compared to unstored cuttings, as the storage temperature
treatments increased from 10◦Cto25◦C, while cuttings stored at 4◦C
for 5 d were similar in quality to unstored cuttings (Arteca et al. 1996).
Impatiens cuttings could be stored for 1 week at 5◦C and still have 100%
rooting, but those stored for 2 weeks had reduced rooting, and those
stored for 3 weeks did not survive storage (Judd 1976). Visual-quality
rating decreased and fresh-weight loss increased when New Guinea
impatiens cuttings were stored at various temperatures increasing from
0.7◦Cto30◦C and from 0 to 5 d in time (Lopez and Runkle 2008b). The
authors noted that cuttings could be successfully stored at 10–20◦Cfor
5 d with limited poststorage impacts; storage temperatures below 10◦C
caused chilling damage and storage temperatures above 20◦C caused
excessive desiccation.
While cold temperatures are best for reducing respiration rate and
improving poststorage performance, some species are sensitive to chill-
ing damage. Symptoms of chilling injury include blackened or water-
soaked tissue, wilted foliage and stems, and/or desiccated tissue from
water loss caused by cellular damage or leaf abscission. Decay will fre-
quently accompany chilling injury; however, the decay may not appear
until the plants are removed from the cooler and re-warmed sometime
after storage (Lopez and Runkle 2008b). Lantana cuttings showed chill-
ing damage when storage temperatures were 2–8◦C for 5 d of storage
(Friedman and Rot 2006).Heliotropiumcuttings, however, only showed
chilling damage when stored at 2◦C for 5 d. Both species showed
less chilling damage when cuttings were harvested at noon versus the