452 



June 15, 1912 



GREENHOUSE PRIMULAS. 



When one considers the great improve- 

 ments, and the remark ihle breaks from the 

 original species that have within the last 

 twenty years or so taken place in the case 

 of Primula sinensis and Primula olxionica, 

 the question arises where, with the vast 

 number of comparatively new Chinese 

 species, will the development of these 

 flowers end ? It is not so many years since 

 that Primula obconica was represented only 

 by the typical kind, a poor little lilac- 

 coloured flower, but now the range in colour 

 is as marked as the size and shape of the 

 individual blossoms. Primula sinensis, too, 

 shows a great divergence from the type and 

 from each other, the massive blooms of the 

 gigantea strain l>eing arranged at one end 

 of the scale, and the light and graceful 

 Star primulas at the other. Another pre- 

 sent-dav feature is the clear and decided 



f ■ 



hues that generally prevail among the 

 flowers, especially if the seed has been se- 

 lected from a good strain. 



Foliage distinctions, too, arc both nume- 

 rous and interesting among tbe varieties 

 of the Chinese primula, for, beside those 

 of the ordinary type, there is what is 

 termed the fern-leaved section ; while in 

 some the stems and midribs are dark- 

 coloured, whoroas in the ordinary form they 

 are green. Again, at a meeting of the 

 Royal Horticultural Society, a group of 

 plants, with leaves som.ewhat resembling 

 those of a pelargonium, was shown. The 

 flowers of these were semi-double and sal- 

 mon in colour. 



Though my horticultural experience ex- 

 tends over many years, I can remember 

 very few plants that have bounded into 

 popularity as rapidly as did Primula mala- 

 coides, a recent introduction from China. 

 The numbers to be seen in the florists' 

 shops in London, and the quantities used 

 for decorative purposes, serve to show that 

 it has gained the confidence of the market 

 grower; than wliich there is no keener 

 critic. The typical lilac-colourerl kind is, 

 as a rule, more grown than the white- 

 flowered variety. Tbe seeds of Primula 

 malacoides germinate readily, and it is in 

 all stages a plnnt of easy culture. As a 

 window plant for the dwelling house, it is 

 just the thing. A\nien one considers the 

 jrreat chaneres that have taken place in 

 Primula obconica since its introduction, 

 the possibility of P. malacoides proving just 

 as amenable, cannot be overlooked. 



The prospect, however, of improving 

 any species by a gradual process of selection, 

 is not the only light in which many of the 

 new primulas may be regarded, for nowa- 

 days so great is the skill of the hybridist, 

 and such an amount of perseverance is 

 brought to bear upon the work, that races 

 'now undreamed of may make their appear- 

 ance in the near future. It is somewba^ 

 singular that the finest of tlie yellow- 

 flowered forms-— Primida Kewensis — should 

 have originated as an accidental hybrid, 

 and still more s ?)gular that, though it was 

 at first barren vet seeds are now readilv 

 obtauied. Wlien such fimdamental chanties 

 as this take place, it is impossible to sav 

 what further surprises await us. At all 

 events, the future of the primula, from 

 all points of view, is in cA'cry wav most 

 promising. W. T. 



excelsa. 



Silver 



Araucaria 



Star. — As a matter of individual taste, I 

 prefer this var'etv of Araucaria excelsa to 

 the newer elegantissima aurea. with folia;o:e 

 a yellowish tinere, which is, however, 

 m ost m a rked in the you n ^ shoots . Thes« 

 last aro in Silver Star almost white; in fact, 

 it iiii irnnroved variety of the older form 

 known as alba ^ipica. — W. T. 



PROPAGATION OF 

 ROCK GARDEN PLANTS. 



The maintenance of a reserve stock of 

 pot-grown plants is of great importance to 

 the up-keep of the rock garden. So many 

 subjects sucx^umb to the dampness experi- 

 enced during the late autumn and winter 

 months that it is quite essential there 

 should be a supply to fall back on. A 

 stock df plants can be raised by the three 

 following methods J viz., seed sowing, cut- 

 tings, and layers, and it is the intention of 

 this note to deal with the two latter 

 methods. 



The propagation of the various subjects 

 by cuttings demands attention during seve- 

 ral months of the year^ commeneing now 

 with aubrietias, alyssums, arabis, etc., and 

 following on with otliers as they cease 

 flowering. A small frame or hand-light is 

 necessary for the purpose, and about six 

 inches of clean sand should l>e' placed 

 within for a rooting medium. This will be 

 found to be the quickest and surest plan 

 of rooting some of the most difficult of 

 plants. The cuttings are prepared in the 

 ordinary way^ and inserted in the bed of 

 sand, well watered in, and kept shaded 

 and close until root-action commences. 

 The quickest way to insert the cuttings is 

 to well water the sand first, then take a 

 piece of glass, and make a cut acroSvS the 

 bed about an inch deej^ to receive the cut- 

 tings. After the latter are placed in posi- 

 tion, by using a little pressure when mak- 

 ing the next cut, the previous one may be 

 closed, and when all the cuttings are put 

 in, a good A\atering will tighten^ them all. 

 The sand will settle down round the bases 



wood attached. All the iberis family root 

 best when the cuttings are taken from the 

 y(uing growths. 



The young, tender shoots of Cynanthus 

 lobatus and Codonopsis ovata quicklv foriii 

 roots when propagat-ed in July."^ The 

 ramondias are increase<l in the same wav 

 as begonias or gloxinias, by leaf propatra- 

 tion. Campanulas may be readilv rai^d 

 from seeds, yet when a true stock of any 

 special species or variety is desired, it is 

 necessary to resort to cuttings, as the 

 colours vary considerably when increased 

 by seeds. Daphne Blagayana, D. cneorum 

 and D. rupestris should be layered, peg- 

 ging the growths into the soil, and' when 

 rooted potting them. This treatment 

 answers for other subjects^ such as Lethmi 

 palustris, Drj^as octo2)ctala. Sliortia gala- 

 cifolia, S. imiflora, Gaultlieria procumbens 

 etc. In fact, there are numbers of plant^ 

 which are not mentioned that will respond 

 to these two methods of propagation, and 

 with the necessary care and attention, a 

 good stock of pot-grown plants is easily 

 obtained. E .C. Pooley. 



Gnaton Gardens. 



POTENTILLAS* 



When so much thought is giA^en to the 

 adornment of the rock garden and the wall 

 irarden it is well to consider the claims 

 the potentillas. Though somewhat lacking 

 the brilliancy of some other rock garden 

 subjects, they furnish us with a group of 

 exceedingly pretty species, well adapted for 

 decorative work. It is often the misfor- 

 tune of rock garden potentillas to be rele- 

 gated to the least prominent positions, 

 resulting naturally in a partial failure as 

 far as effect is concerned. Brin": them out 



quite closely^ making them absolutely air- 

 tight. On no account must the sand be 

 allowed to become dry, or failure is sure to 

 fellow. Immediately the cuttings are 

 rooted, they must be carefully lifted and 



into small pots, rowing them in needs, and they will give many effective 



into the front rank of the rock dwellers, 

 provide them a situation suitable for their 



put 

 f 1 ames until 



pots, growing 

 established. 



Successfid propagation depends a great 

 deal on the right sort of cuttings being 

 taken, for, whilst those of some plants root 

 best from young growths, older and harder 

 wood of others will be found most suitable 

 for the purpose. A commencement should 

 be made with arabis, and at this season 

 there is usually an abundance of young 

 shoots, which form splendid cuttings. To 

 obtain good material for the purpose when 

 dealing with the aubrietias, it is necessary 

 to cut the plants back when flowering 

 ceases, and young shoots are then produced 

 from the base of the plants. These shoots 

 root freely when taken off about two inches 

 long, and trimmed in the ordinary way. 

 The alyssums root freely when a heel " or 

 portion of the old wood is allowed to re- 

 main on the shoot. Lithospermum pros- 

 tratum is rather a difficult subject t^ pro- 

 pagate from cuttings, j^et if the young 

 growths are detached from the plant by 

 gently pulling them off, tbey root readily 

 in the sand. 



Androsace lanuginosa is easily rooted in 

 the same way, and nice little ])lants are 

 thus obtained for planting out in the follow- 

 ing spring. Androsace sarmentosa and A. 

 Chumbyi are most successfully propa- 

 gated by pressing the rosettes into the soil 

 and I>^gging them down, without removing 

 them from the plant. When rooted the 

 rosettes are lifted and potted. The various 

 members of the Rock Pink family root 

 freely from slips— that is, the shoots drawn 

 off and inserted in the sand without being 

 trimmed at all. Phlox subulata and setacea 

 are increased either by cuttings of the 

 voung growths, or by l^gg'ng pieces down 

 into some fresh soil. The heliantluuuums 

 respond readily to the cutting treatment, 



and these should have a portion of the older 



pictures, which will be worthy of the con- 

 templati.m of any garden lover. 



It may be remarked in passing that our 

 subjects are chiefly sun-lovers, delighting in 

 a fairly open situation, with a good light 

 sandy soil as a rooting mediinn, wh'le their 

 culture is of the easiest possible character. 

 Grown in the open points of a stone wall, 

 many of the potentillas give fine sheets of 

 foliage and blossoms, which for length of 

 duration have few equals. 



Picture P. Tonguei in such a position, 

 with its trailing growths hanging pendant- 

 w'se down the wall face, and studded with 

 a host of exquisite terra-cotta, crimson- 

 marked blossoms. Or, P. ambigua, with its 

 dense masses of rich greenery, clouded over 

 with a golden haze of bright blossoms, is 

 equally charming in its own way. P. flagel- 

 laris, too, is very pretty, with its trailing 

 stems stealing do^vn the rock face^ and its 

 short-stemmed yellow blossoms, singly, but 

 freely, produced. 



Or go a step further, and try the effect 

 of P. nepalensis, or, better still, its variety 

 Miss AVillmott, in a similar ])osit on, tn^ 

 profusion of rosy-pink blassoms given hy 

 the latter is especially fine. Or try the 

 charming P. Hopwoodiana from the wall 

 to]), or a well set-up ])os:tion among the 

 rocks, aud note the effect of yellowish-butt 

 and rosy-cai-mine blossoms. P. glandulosa, 

 a bright golden-yellow Californian species, 

 will succeed best in a situation as note(l, 

 and the forms of the charming P. "i^ida 

 will also do well, if not too hot and <lry. 



Speaking of P. nitida, may I renun<l the 

 reader that this is one 'of the most exqui- 

 site of all rock plants, carrying pretty ter- 

 nate silverv loaves and pale rosy flowers. 

 It spreads bv means of undergjound stem. . 

 and reallv should be foiuul in all c()lk-:^tion^ 

 of rock ])lants. Its varieties are alba, a 



