292 



THE DICTIONARY OF GARDENING, 



Rhododendron continued. 



Rhododendron may be increased namely, seeds, cuttings, 

 and layers, and by grafting. Budding and inarching 

 are also practicable. The seeds, which are very minute, 

 require to be sown in thoroughly-drained pots, or 

 shallow pans, of sandy peat. The top layer should 

 have a little more sand intermixed than is necessary 

 for the other portion, and should be passed through 

 a fine sieve. After the surface has been rendered 

 smooth and pressed firm, the pots, or pans, should be 

 watered previous to sowing, and then allowed to drain. 

 Scatter the seeds thinly over the top, press in, and 

 cover very lightly with a little silver sand. To pre- 

 vent the soil from drying too readily, the plan of 

 placing a little moss over the soil is often practised ; 

 this must not be allowed to remain after the seeds 

 begin to germinate. The pans may be placed in gentle 

 heat, or in a cold frame ; and shading from sunshine is 

 necessary. February and March are the best seasons 

 for sowing. When the plants come up, and are large 

 enough to handle, they should be pricked off in pans of 

 soil similar to that in which they have previously been 

 growing, and be kept shaded and close until re-established. 

 Afterwards, they may gradually have air and light ad- 

 mitted to harden them. Cuttings intended for pro- 

 pagating should be made of partially-ripened wood, in- 

 serted in sandy peat, and kept close and shaded. After 

 they have callnsed, a slightly higher temperature may 

 be allowed than at first, such as a gentle hotbed affords. 

 Layering may be practised in autumn or spring, when 

 the parent plant is sufficiently dwarf to allow of its 

 being done. Eoots proceed from almost any part of the 

 firm wood near the base, but only very slowly indeed. 

 Grafting is one of the principal methods adopted for in- 

 creasing established varieties of Rhododendron, the stocks 

 used being procured from seedlings or cuttings obtained 

 from medium or strong-growing common varieties or 

 species of good constitution. Grafting is most exten- 

 sively practised towards the latter part of summer, when 

 the scions have become ripened; with the tender indoor 

 species, it is best done in winter. Grafted plants re- 

 quire to be kept for a time in close frames until a 

 union has been effected. 



Culture of Indoor Greenhouse Rhododendrons. Many 

 of these develop into very large bushes, where space 

 can be afforded, and provision made for planting them 

 out. Amongst the species may be specially mentioned 

 the magnificent R. Nuttallii, also R. arboreum, R. Auck- 

 landii, R. Edgeworthii, &c. An open, peaty soil suits 

 best, and good drainage is essential, as large quantities 

 of water are requisite in summer. Unless seeds are re- 

 quired, the whole of the seed-vessels should be carefully 

 removed when flowering is over, and the plants should 

 then, if possible, be kept rather close while making their 

 annual growth. Specimens of the species above-named 

 may also be grown successfully in large tubs or pots, 

 as the root space required is not really so much as 

 the size of head would suggest. All the beautiful 

 hybrid greenhouse Ehododendrons are most desirable 

 subjects for decorative purposes in cool houses. They 

 are mostly free-growing, and exceptionally free-flowering, 

 as, by affording what is known as a warm greenhouse 

 temperature, some of the plants in a collection are 

 nearly always to be seen in flower. Especially are 

 these remarks applicable to the section raised from 

 R. jasminiflorum, R. javanicum, &c., which require more 

 heat in winter than R. ciliatum, R. Edgeworthii, and 

 others mentioned above. The hybrids succeed in rather 

 small pots ; good turfy peat and some silver sand is the 

 most suitable compost to use. The plants should be kept 

 under glass, but subjected to plenty of air in summer 

 after their annual growth has been made. Water must 

 be very carefully administered, particularly after pot- 

 ting, or if signs of ill-health are apparent. Eain-water 



Rhododendron continued. 



for these, as for all other hard-wooded plants, is much 

 to be preferred to any other. 



Culture of Hardy Outdoor Rhododendrons. Hardy 

 Ehododendrons succeed under various conditions regard- 

 ing situation and soil, but one thing is always fatal to 

 the well-doing of most of them, namely, the presence of 

 lime or chalk in the compost within reach of their roots. 

 Naturally, they prefer a rather moist situation and 

 partial shade, but these conditions are not absolutely 

 necessary, as the plants are hardy enough to grow and 

 flower splendidly where fully exposed to the sun. Peat 

 and leaf soil are unquestionably best suited for Ehodo- 

 dendrons ; but R. ponticum and its numerous beautiful 

 varieties grow well where there is a good proportion of 

 loam, provided the destructive ingredients already re- 

 ferred to are absent. It is generally necessary to have 

 beds specially prepared for these plants, by taking out 

 the ordinary soil and refilling with a prepared compost, 

 If peat is procurable, it should form the bulk ; leaf soil 

 and sandy loam may be added more freely when they can 

 be obtained more easily. Dried cow-manure is also a 

 good addition. Prepared beds for Ehododendrons should, 

 if possible, be from 2ft. to 2ft. deep ; it is far better 

 to make them properly at first, and large plants require 

 that depth, although they always root near the surface. 

 Transplanting may best be performed in spring; but 

 there are few shrubs that withstand it so well at any 

 season, provided the balls are not kept long out of the 

 ground, and watering is well attended to afterwards. 

 Large standard specimens of the numerous beautiful 

 hybrids are exceedingly telling in pleasure-grounds, either 

 isolated or planted amongst other smaller plants of Eho- 

 dodendrons, or such subjects as are usually grown with 

 them, hardy Ericas, Kalmias, Pieris, &c. The ponticum 

 hybrids form valuable forcing subjects; they may be 

 lifted from the open ground after the flower buds are 

 set, and potted up. If introduced to heat in early spring, 

 the flowers soon expand, and showy specimens are 

 thereby obtained early for greenhouse decoration. 



R. ferrugineum and R. hirsutum are dwarf, free-flower- 

 ing species, well adapted for planting in small beds by 

 themselves, or in prepared borders in different parts of 

 rock-gardens, &c. They are always dwarf and some- 

 what slow-growing, so that, if associated with the vigorous 

 ponticum varieties, they are liable to become overgrown 

 and smothered. All Ehododendrons have extremely 

 small, fibre-like roots, which are disposed very close to, 

 and even on, the surface of the soil. It is important 

 that these be kept protected from the sun ; if the foliage 

 does not insure sufficient shade, a top-dressing of leaf 

 soil, cocoanut-fibre refuse, or similar material, proves of 

 great advantage through the summer time, when the 

 roots require to be kept cool and moist. 



The best-known species and varieties are described 

 below. Except where otherwise indicated, all are shrubs, 

 and require greenhouse treatment. 

 R. aeruginosum (verdigris-coloured). A synonym of R. campanu- 



latum. 



R. alblflorum (white-flowered), fl. drooping, on fascicled, rarely 

 solitary peduncles ; calyx large, deeply cut into five brownish- 

 green segments ; corolla pure cream-white, twice as long as the 

 calyx, rotate-campanulate, flve-lobed ; stamens ten, included. 

 July. I. deciduous, elliptic-lanceolate, shortly petiolate, entire, 

 glabrous, penninerved, lin. to liin. long ; stipules brown, early 

 deciduous. Branches erect, h. 2ft. to 3ft. Rocky Mountains. 

 Hardy. (B. M. 3670.) 



R. album (white). /. small, on pedicels lin. to liin. long ; calyx 

 minute ; corolla pale yellowish-white or cream-colour, broad- 

 campanulate, its five lobes nearly equal, rounded, retuse ; stamens 

 ten ; corymbs umbellate, terminal, shorter than the leaves. 

 November. I. rather copious, spreading, 3in. to 4in. long, oblong- 

 lanceolate, acute, on short, lepidoted petioles, glabrous and dark 

 green above, thickly clothed with minute, ferruginous scales 

 beneath. Branches clothed with reddish-brown bark. h. 1ft. 

 Java. (B. M. 4972.) 



R. Anthopogon (bearded-flowered).* fl. sulphur-coloured, glo- 

 merate ; calyx with a short, nve-lobed litnb ; corolla salver-shaped, 



