148 J.E. FAUST, J.M. DOLE, AND R.G. LOPEZ
in cases where temperature abuse has occurred during transport. For
example, if the temperature of the box heats up due to excessive expo-
sure to high temperatures in transit and then the box is put into a cooler,
then the heat inside the insulated box fails to adequately dissipate out
of the box due to the insulation.
Cuttings are placed in plastic bags by cultivar (one cultivar per bag)
or arranged in wax-coated cardboard trays. Depending on cutting size,
there are normally 50–200 unrooted cuttings per bag or tray, whereas
callused cuttings are packed at a lower density. The cuttings may be
wrapped in moistened paper to reduce cutting desiccation during ship-
ment. Holes may be poked into the bags to increase ventilation within
the package, reduce ethylene and carbon dioxide accumulation, and
reduce oxygen depletion in the package. Insufficient hole size can result
in the accumulation of ethylene and carbon dioxide, which cause dele-
terious effects on postharvest longevity and propagation performance.
Excessively large holes can result in rapid water loss and cutting dehy-
drations. Anaerobic conditions have not been observed within packages
of unrooted cuttings. The appropriate hole sizing depends on the fresh
mass of the cuttings inside the bag with the recommended range being
0.5–5.0 g⋅mm−^2 (total hole area)/g fresh mass (J.E. Faust, unpublished).
IV. CUTTING MANAGEMENT AND PROPAGATION
The propagation and rooting success of herbaceous cuttings by green-
house growers has become highly dependent on the quality of harvested
cuttings, postharvest environmental conditions, and duration of ship-
ping and storage. This is in addition to the numerous endogenous and
exogenous factors that influence callus formation, adventitious root ini-
tiation, and development of unrooted cuttings (Haissig 1986). Endoge-
nous factors include genetics (Haissig 1986), hormones (Jarvis 1986;
Ahkami et al. 2008), mineral nutrition (Blazich 1988; Gibson 2006), car-
bohydrates (Rapaka et al. 2005; Druege 2009; Currey and Lopez 2015),
and gas exchange (Grange and Loach 1983; Davis 1988; Svenson et al.
1995; Wilkerson et al. 2005a; Currey and Lopez 2015). Exogenous fac-
tors include substrate and air temperatures (Andersen 1986; Wilkerson
et al. 2005b; Blanchard et al. 2006), water (Loach 1988), exogenous hor-
mone applications (Whipker et al. 2006; Currey et al. 2013a), mineral
nutrients (Santos et al. 2008; Fisher et al. 2009; Currey and Lopez 2014),
and photosynthetic light quantity and quality (Lopez and Runkle 2008a;
Currey et al. 2012; Currey and Lopez 2013).
Once unrooted cuttings are received by the grower, propagation can
be divided into five distinct stages: Stage0–Preparationforcutting