164 ALPINE PLANTS 
must write at present, for they are not within the legiti- 
mate scope of this work, albeit the large flowered Pentste- 
mons do sometimes find their uses in large rock gardens 
or where a rock bank merges into a broad expanse of 
border perennials. There are, however, quite a large 
number of dwarf-growing species with comparatively 
small but strikingly coloured flowers, and which in char- 
acter, habit of growth, and hardiness are appropriate 
for the collection of alpine and kindred rock plants. The 
majority are of American nativity, but come from the 
higher altitudes, the Rocky Mountains giving us some, 
and a few coming from Mexico. A few kinds are not 
absolutely hardy, but on the whole my experience of the 
Pentstemons is that they generally get more coddling 
than is good for them, and provided they are given 
thoroughly good drainage, with plenty of grit in the soil, 
most of them will pass through our winters unharmed, 
and even where frost kills the stems the stools throw up 
vigorous new growth in spring. 
The sub-shrubby kinds are easily propagated from 
cuttings of the young growth, either in spring or in early 
autumn, the latter being given the protection of a cold 
frame during their first winter. A few make tufted growth 
of a herbaceous character, and these may be divided and 
* transplanted in spring. Seed also affords a means of rapid 
increase of stock, but in most cases the seedlings are prone 
to considerable variation in colour and form, and it is 
advisable to select the best forms and purest colours for 
further increase from cuttings. 
P. heterophyllus is one of the most pleasing for either 
