The selection of suitable alpines, perennials and shrubs and trees also necessitates considerable knowledge on the part of the gardener.
Many of the little alpines may be brought into the front line planted between suitable pieces of stone, or they may be relegated to a particular spot, and placed on an artificial rockery.
Another very distinct group with silvery foliage - the crustaceous group - contains some of our choicest Alpines.
The glasshouses contain collections of palms, rare cycads, tropical ferns, cacti and alpines.
This beautiful "Catchfly" is not often seen even among the choicer alpines, while colonies of it in the rock garden are, rare.