3.3.1.2 Propagation Through Seeds
For cultivation ofCannabis, seeds has been the main source of propagation. Well
aerated and moist soil is preferred for sowing seeds in small jiffy pots. During the
cold weather, an electric heat mat can be used under the pots to increase the
temperature. The seedling should begin to sprout by fourth day and most of the
viable seeds germinate by two weeks.
Variation in the rate of seed germination depends on the variety, seed age,
storage condition and, soil and water temperatures.Cannabiscultivated outdoors
need full sunlight to grow profusely, mature properly and to produce high resin
content. Germinated seedlings can be kept under coolfluorescent light with 18 h
photoperiod till the seedlings are big enough to transplant in bigger pots. These pots
can be kept under full spectrum grow light (18 h vegetative photoperiod). After
enough vegetative growth, plants may be exposed to 12 h photoperiod forflow-
ering. Onset offlowering normally occurs in two weeks. At this stage, male plants
can be identified. Since maleflowers appear before femaleflowers, male plants be
immediately separated from the female plants if sinsemilla buds are to be produced.
Cuttings can be taken from the vegetative branches of selected high yielding female
plants (based on early GC-FID analysis) and can be kept under vegetative stage for
future propagation.
3.3.1.3 Vegetative Propagation
Vegetative propagation, also referred as cloning, the technique of growing plants
from cuttings from a selected mother plant is a great way to generate crop of
consistent quality. Once, a particular clone is screened and selected, a fresh nodal
segment about 6–10 cm in length containing at least two nodes from the mother
plant can be used for vegetative/conventional propagation either in solid (soil) or in
liquid medium (hydroponics) (Fig.3.7). Micropropagation, an in vitro vegetative
propagation technique can also be used for the mass-propagation ofC. sativa(Fisse
et al. 1981 ; Hartsel et al. 1983 ; Braemer and Paris 1987 ; Mandolino and Ranalli
1999 ; Feeney and Punja 2003 ; Slusarkiewicz-Jarzina et al. 2005 ; Bing et al. 2007 ;
Lata et al.2009a,b; Wang et al. 2009 ; Lata et al. 2010 ).
3.3.1.4 Hydroponics Propagation
Hydroponics is used by many cultivators under outdoor as well as indoor growing
conditions. The importance lies in the fact that the plants are always watered with a
balanced nutrient solution. These systems use a growing media such as rock wool
or hydrotone clay balls in the standard one gallon growing plastic containers
(Fig.3.8). The use of rock wool not only provides excellent aeration, but also
3 Cannabis sativaL.: Botany and Horticulture 89