PROPAGATION BY CUTTINGS. 



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As most greenhouse plants are increased by cuttings, it 

 will be useful to mention that they are generally selected 

 from the shoots of one season's growth, and care must be 

 taken that there is one joint (the part from which the leaves 

 proceed) above the surface of the ground, and another be- 

 low, from which the leaves must be cut ; this lower joint 

 sends forth new roots when placed in earth suitably pre- 

 pared for it, and the stimulus is generally given of what is 

 called by gardeners bottom-heat, by placing the pot in a hot- 

 bed, though this is not always necessary. These cuttings 

 should be covered by a bell-glass, and the moisture which 

 settles on the inside wiped away every day, or the young 

 plants will suffer ; when they seem thoroughly established, 

 the glass should be raised a little every day, that they may 

 be hardened. 



Some plants which do not succeed so well from cuttings 

 absolutely severed from the parent branch, are increased by 

 layering, which is done by bending the branch down into a 

 pot or on to the surface of the ground, and pegging it down 

 firmly ; it then sends forth roots at the bent part (which in 

 some plants has to be notched or twisted), where the sap is 

 interrupted in its flow ; after these roots are fully established, 

 the young plant becomes independent, and may be separated. 



