38 ALPINE PLANTS 
single row of plants, the perpendicular face of the wall 
can be made to accommodate scores of different kinds 
of plants, affording an ever-changing spectacle of beauty 
that will go on developing and improving year by year. 
The best season for construction of wall gardens is early 
autumn, for at this season the plants may be placed in 
position as building proceeds, and will then have opportunity 
to well establish themselves and get their new roots well 
behind the stones before scorching summer’s sun has to be 
endured. 
Of course a wall situated in a cool shady spot can be planted 
during spring with every chance of success, but where circum- 
stances call for spring planting of a wall exposed to midday 
sunshine it will be a wise precaution to erect some sort of 
temporary shading until the plants have taken good root 
hold. 
