... and yet a major problem with [lots] of roses is that, while they may have wonderful flowers, they do not usually make wonderful plants. [One way] Miss Jekyll overcame this problem was by "... leavening the scheme with plants other than roses, in particular grey-leaved plants...". One frequently used grey-leaved plant was Catmint [Nepeta x cultivars].
Note: She used Catmint, not Catnip.
"Greay-leaved plants offer fineness of texture and a softness of colouring which harmonizes with the whole colour range of rose flowers...
Furthermore, many of the grey-leaved plants retain their foliage throughout the year, furnishing the garden when the roses are reduced to bare sticks.
The rose garden may be designed to display roses, but that should not prevent its being attractive at other times of year."
'White Meidiland' is an excellent rose for any size garden. It normally grows to about 2.5-3 feet in height... but it spreads to about 5 feet. The blooms appear in clusters and can literally cloth the plant in white. Its blooms are almost snow white and have 33-50 petals. They also make good cut flowers: