36 Commercial Gardening 



scarlet tints in autumn, especially in the variety called splendens. Sprays 

 of foliage are largely used by florists. Another North American Oak 

 with deeply coloured leaves in autumn is Q. rubra, to which may be 

 added Q. palustris and Q. tinctoria. 



With the exception of special varieties which are grafted, most Oaks 

 are easily raised from seeds. Hundreds of thousands of the Common Oak 

 are raised annually. 



Rhamnus (BUCKTHORN). Of the sixty species known, only two or 

 three are commercially valuable. The Common British Buckthorn (R. 

 catharticus), 5-10 ft. high, with ovate serrate leaves; the Black Dogwood 

 (R. Frangula), with entire leaves; and R. Alaternus, from South Europe, 

 with ovate - elliptic serrate leaves, are best known. There are several 

 varieties of the last two named. The plants grow in any garden soil, 

 and are raised from seeds, cuttings, and layers. 



Rhododendron. The trade in Rhododendrons is extensive, and of 

 late years many fine garden forms have been raised. Even the com- 

 monest kinds are gorgeous when carrying their clusters of tubular or 

 bell-shaped flowers; but those with large blooms and clear and distinct 

 colours are naturally most appreciated, especially if they are also hardy 

 enough to stand our ordinary winters. The now common R. ponticum, 

 from Asia Minor, has proved itself so valuable, not only as stock for the 

 grafting of the choicer varieties, but as a game-covert plant, that it is 

 raised in enormous numbers every year from seeds. Other kinds are 

 largely used in the same way, and all possess the great advantage that 

 they are immune from the attacks of rabbits. In the most favoured 

 parts of the kingdom, like Devonshire and Cornwall, many parts of 

 Ireland, and the south-west of Scotland many of the lovely Himalayan 

 Rhododendrons flourish as if they were indigenous. Some valuable 

 hybrids have been raised from these. 



The old idea that Rhododendrons would flourish in a peaty soil only, 

 and in no other, no longer holds good. Nurserymen now grow them in 

 loam as well as in peat; but the main point is to refrain from adding 

 lime to the soil in any form, and not to plant on a limestone soil. 



Amongst the Himalayan Rhododendrons hardy in the milder parts 

 are the following: arboreum, white, rose, or crimson, March to May; 

 Aucklandi, pure white tinted with pink; barbatum, crimson; campanu- 

 latum, pale lilac, spotted purple; ciliatum, reddish purple; Dalhousice, 

 white, tinged rose; Falconeri, white; fidgens, blood red; grande, white; 

 Hookeri, deep red; niveum, yellowish and lilac, spotted crimson; Thomsoni, 

 blood red; and others. 



Some very fine hybrids have been raised from some of these species 

 and others, the best known being Harrisi (arboreum x Thomsoni); 

 Kewense (Aucklandi x Hookeri); Luscombei (Fortunei x Thomsoni); 

 Nobleanum (arboreum x caucasicum), which produces its crimson flowers 

 in January and February; prcecox (ciliatum x dauricum); Shilsoni (bar- 

 batum X Thomsoni); Wilsoni (ciliatum x glaucum); and several others. 



