260 



GARDENERS' CHRONICLE 



The Rock Garden 



ARTHUR SMITH 



(Coiilinucd from the .liigust issue.) 



THE following' descriptive list of alpines and other 

 plants suitable tor a rock garden must not be con- 

 sidered in an)' way complete, a brief selection only 

 has been made of those considered best for American con- 

 ditions, all of which have been cultivated by British 

 specialists m rock plants for many years. In the case of 

 several genera, hxbridizers have been at work for some 

 time and varieties have been raised which in a number of 

 instances ha\e proved to be more at home in lowland 

 gardens than their types. 



Accrna micropliylla. This is attractive by reason of its 

 sshowy crimson spines which are borne on the calyx. It 

 has several distinct varieties and is used as an evergreen 

 ground cover over bulbs. Spreads by creeping rootlets 

 and may be propagated by division, seed and cuttings. 

 (Xative of Xew Zealand.) 



Acaiitlwlivioii glumcreiim. Height six inches; leaves 

 evergreen. This has the advantage of blooming later than 

 most kinds. July to September. It has rose-colored flow- 

 ers. Slow growing and requires all the sun possible. 

 Propagated by seeds, which are slow in germinating ; by 

 cuttings made in late Summer and wintered in a cold 

 frame; division is possible, but it does not take kindly to 

 this method. (Armenia.) 



Acliillea. Most of this genus are too coarse for the 

 rockery, but tomentosa, with its downy foliage and yellow 

 flowers, has a distinctive effect, especially against red sand- 

 stone rocks. This is native both of this country and of 

 Europe. A. rupcstris. considered Ijy some a better kind, 

 has white flowers. (Xative of Italy.) 



Adonis vertialis. This has showy, large yellow flowers 

 :n early Spring. While not classed among the choicest of 

 alpines, it is an easy doer and readily raised from seed. 

 (Apennine Mountains.) Other species are aiiiiirensis 

 and pyrrcnaica. 



Aithionema pulehcUum. Flowers pink. May and June; 

 leaves glaucous. This is a beautiful plant allied to Ihcris. 

 and easily propagated by division in the .\utunm. Should 

 have a sunny position. (Central Asia.) 



Alyssum saxatile compactiim. Well known, and one of 

 the most jiopular of rock plants. .\s its name suggests, the 

 variety compactiim is closer growing and therefore more 

 suitable for rock gardening than the original. Th.ere arc 

 several other forms having dilicrent shades of yellow 

 flowers, and one with double flowers and variegated foli- 

 age, but none are really better than the above. Easily 

 grown from seed. 



Andromeda poUjolia and glaiicopliylla. These small 

 native sub-shru1)s are not so well known as their beauty 

 deserves. They should have at least some shade, with 

 plenty of leaf mold or peat in the soil. They have neat 

 and compact growth, but become rather too large for a 

 small rockery. 



Androsacca. Rock Jasmine. Alpine Phlox. X^o genus 

 of the mountain flora is more charming than this. It is 

 principally found in the higher ranges of the Euro])can 

 Alps and Pyrenees, and there are one or two species on 

 the Himalayas. They are not of the easiest culture and 

 it is useless to attem|)t growing them unless the air is 

 absolutely pure at all times, for they will soon die in the 

 neighborhood of towns. They like a little shade, from an 

 overhanging rock, for instance, that is sufficient to shelter 

 them from the middav sun. 'i'hev slKJiild alwavs have 



small stones placed around their collars. Propagation is 

 by seed sown in ])ans, and by division in Autumn. 



The most po])ular spe<."ies is cornea, having llesh-colored 

 flowers with yellow eye and is a most beautiful species. It 

 has trailing shoots. (Himalayas.) Sarmcntosa is a charm- 

 ing plant also from the Himalayas. It is of rather small 

 growth and should be covered with glass during the Win- 

 ter. Limestone chips are the best to use around its collar ; 

 "iillosa is a great favorite with alpine growers in Britain. 

 it has gray leaves thickly covered with fine hairs and its 

 pink flowers are borne in umbels. This species should 

 have some broken limestone mi.xed with its soil. Among 

 other species are chamccjasiiie with crimson flowers, also 

 liking limestone; glaciaUs, very dwarf, with pink flowers, 

 rather difficult to grow ; Uliosa is a vigorous grower with 

 rose-colored flowers, likes lime ; zntaliana is distinctive by 

 reason of its yellow flowers, and is a delightful object 

 when nestling in a rock crevice ; dislikes lime. 



Anemone. Most botanists today place the lovely native 

 Hepatiea triloba in this genus. It is splendid for the rock- 

 ery provided a shaded spot can be found for it, and is one 

 of the most valuable and earliest of Spring flowers, and the 

 coppery tint which its foliage puts on in Winter produces 

 a beautiful effect at that season. It is common in our 

 eastern woods among rocks, from whence it can be easily 

 collected, as it trans])lants readily, but care should be taken 

 that its roots are not doubled tip in replanting. It is native 

 from Labrador to Florida. A. fiilgcns has scarlet flowers 

 in May and June and makes a brilliant spot of color, and 

 it is a vigorous grower ; occidentalis, also known as alplna, 

 is a western native species with bluisii-white flowers in 

 May , it thrives best when limestone is mixed witli the soil. 

 All Anemones can be increased both bv seed and divisions. 



Aqiiilegia. i\fost of this beautiful genus are too tall for 

 rockeries, but there are several alpine and sub-alpine 

 species, native of Xorth America as well as of Europe and 

 of Asia, which can be used. Alpina is native of the Swiss 

 Alps and has blue flowers ; glandulosa is another dwarf 

 species from Siberia and is one of the handsomest ; it has 

 blue and white flowers; a variety of this, known as sluarli, 

 is equally charming and longer lived than its parent; 

 jonesii is the dwarfest and most tufted of t'olumbincs: it 

 has blue flowers in July and is native of Wyoming and 

 Montana. Xonc of this genus are really long lived plants 

 as perennials go, but as they are easily raised from seed 

 there is no difificultiy in keeping up a stock of them. 



Arctostapliylos. This is allied to the Trailing Arlmtus. 

 and like it, evergreen. There arc several sjiecies native of 

 .\nierica. but only a few, which are mostly trailing, are 

 harfly in the northern states, these being ciuite good for 

 rockeries. The llowers are small, white tinged with red, 

 but the chief value of these plants is for the effect of the 

 red fruit, which persists during .'Vutumn and early Winter. 

 The hardiest species are: Ufa-ursi. I'.earberry, native all 

 over the northern .States and south to Mexico; ncivden^sis, 

 founci on the higher mountains of California, has larger 

 flowers and foliage and slunild onlv be used where there is 

 plenty ol room ; tomentosa is a more upright species native 

 of the iKirihwest; alpina. the smallest, grows as far north 

 as the .\rctic regions. T.-irlial shade is l)encficial to them, 

 and when nf)t covered with snow, light protectimi fmni 

 Winter sun is advisable. l'ro])agation is by cuttings of 

 mature wood taken late in .'■Summer and rooted under glass. 



Arnehia eehiodes. Prophet i'-lowcr. This is remarkable 

 for the five dots which il h,is upon its yellow flowers, black 



