282 ROCK GARDENS 



G. tinctoria^fi. pi. — A compact, dwarf-growing, deciduous shrub, 

 about 12 inches high, of spreading habit and fairly rapid growth. 

 Profusion of yellow flowers in the summer. Very useful and attractive. 

 There is a single form, but the double is the better of the two. 



Gentiana (Gentianaceae), Gentian 



A very numerous genus of mountain plants, amongst which are 

 some gems for the rock garden. I shall deal only with the 

 perennial, for although there are many annual and biennial kinds, 

 their beauty is of too fleeting a nature to be suitable for our 

 purpose. The perennial kinds are, unfortunately, all somewhat 

 unreliable in cultivation, growing like weeds in some places, while 

 in others, under apparently similar conditions, unaccountably 

 pining away in a short time. They all exceedingly dislike dis- 

 turbance, and drought at certain times of the year is fatal 

 to them. 



G. acaulis (" Gentianella "). — South-east or south-westerly aspect, 

 on slight slope. Loam, plentifully mixed with limestone and gravel, 

 and well drained, though not so as to render the soil very dry. It 

 forms a dense carpet of compact tufts of glossy green leaves, from 

 which rise large tubular, deep blue flowers, in the spring and 

 summer. Quite hardy, and increased by division. This plant is 

 the well-known " Gentianella," than which no more lovely plant 

 can be found in the rock garden. It is, however, very uncertain in 

 cultivation, for while in some places it will grow and flower freely 

 without the least trouble, in others no amount of care will make it 

 thrive. One thing specially to observe is to plant it deep and as 

 firmly as possible : to this particular attention should be paid. 

 With me, a gravel walk is what it revels in. It is also a good plan 

 to put chips of stones over the surface of the ground, which helps 

 to retain the necessary moisture, and amongst which its shoots like 

 to ramble. If the weather be very dry during the spring and 

 summer, it should be watered freely. It is difficult to lay down 

 any rules for its cultivation, for what appears to suit it in one garden 

 will not do so in another ; but if the above directions are carried 

 out, there is ever}' reason to expect success. There is also a white 

 form, which is not so pretty as the type. 



Very nearly akin to G. acaulis^ and which may almost be taken as 

 varieties of it, are alpina^ which is rather smaller. Angustifolia, 

 deep blue throat and spotted with green. Clusii^ very similar to 

 alpifui^ has lanceolate leaves and very dark blue flowers. Coelestina, 

 sky-blue, with interior of throat white. Kochia7ia^ elliptic-shaped 

 leaves and flowers spotted with black. All like a limestone soil, 

 except the last-named, which requires a soil free of it. 



