600 



GARDENERS' CHRONICLE 



is a sufficient refutation of the wail of the croaker that we 

 cannot grow alpines. In this list there are about eighty 

 species and varieties of Saxifraga, over forty of them be- 

 longing in the Encrusted section, and twenty in the "reck- 

 oned to be difificult" Kabschia group. There are ten 

 Androsaces, half a dozen or more Aethionemas, a dozen 

 Campanulas of choice dwarf types, more than a score of 

 Sedums, and representatives of such typical alpines as 

 Dryas, Draba, Ramondia, Gentiana, etc. 



Merely to mention the lesser known species that ought 

 to be considered indispensable in a well planted rock gar- 

 den would take up far too much room, and, because of" the 

 supreme unattractiveness of a mere list of names, would 

 probably defeat the purpose we have in mind — that of 

 convincing the reader of the desirability of increasing the 

 number of rightful occupants of the rock garden and the 

 exclusion of arrogant interlopers. Therefore on this occa- 

 sion a few only of the lesser known but eminently desir- 

 able kinds will be considered. 



When the genus Achillea is mentioned the species that 

 usually are the first to come to mind are A. filipcnduUna, 

 and the A. ptannka varieties — admirable in the herbace- 

 ous border, but, because of their rampant growth, anath- 

 ema in the rock garden. Or we may think ruefully of 

 that pernicious weed that thrives amazingly in lawns 

 made on poor dry soil, A. millefolium, the Common Yar- 

 row. But this is a large genus and includes many charm- 

 ing rock and alpine plants. The gem of the genus is 

 A. umbellata, from Greece, which forms mats of deeply 

 cut silvery leaves topped with white flowers five or six 

 inches high. A. argentea is a similar species and A. cla- 

 vencr is a tufted species with ashy leaves and white flowers. 

 The species usually sold as A. ageratifolia or as /4. ager- 

 atifolia var. aizoon is not an Achillea at all but is cor- 

 rectly Anthcmi<: aizoon. In spite of spending most of its 

 time under an alias it is far from being an undesirable 

 and is by many considered to be the best of the dwarf 

 Composites with silvery leaves and white flowers. It has 

 white leaves, very attractive, and useful for providing foli- 

 age contrasts associated with plants having leaves of 

 bright green. Its flowers are large, produced in umbels 

 arising on wiry stems about ten inches from the ground. 

 The white, or whitish, centers of the flowers of the plants 

 just mentioned cause them to stand out distinctlv from the 

 rest of the family whose disk florets are usually yellow 

 or brown and but rarely white. 



A dry sunny slope, well drained, is the best position in 

 which to grow these hoary leaved plants. They bitterly 

 resent wet feet and too much water over head. Although 

 it is not always practicable to prevent the latter it is easily 

 possible by providing ample drainage and porous soil to 

 ensure the right conditions about their roots. A few 

 years ago we sufi^ered from ten consecutive days of al- 

 most continuous rain coupled with high temperatures and 

 humidity. When the heavens ceased to weep our collec- 

 tion of Achilleas presented a sorry spectacle with leaves 

 rotted and matted together, bedraggled and forlorn. But 

 in spite of this ordeal, which worked havoc on many 

 plants better able to endure such copious rainfall, we 

 managed to save those of the Achilleas planted where 

 super drainage prevailed. 



The genus Androsace contains many species that are 

 at once the joy and the despair of the' alpine enthusiast. 

 Joy giving becuse of their dainty, diminutive perfection, 

 and despair provoking because of their abhorrence of our 

 hospitality which is expressed bv their prompt demise. 

 Fortunately not all of them are so unappreciative of our 

 efforts on their behalf. Some of the Himalayan repre- 

 sentatives are easy. Our favorite is A. lanuginosa, part- 

 ly because of its habit of blooming all through the Sum- 



mer. It is a delightful plant with trailing stems, its 

 leaves clothed with silky hairs, and flowers of rosy-lilac 

 produced in umbels. There is a variety. Leichtlinii, which 

 has white blooms with red or yellow' centers. Cuttings, 

 about two inches in length, m'ade from the tips of the 

 shoots, root readily if inserted in sand in a cold frame in 

 August. Another species from the Himalayas is A. 

 sarmentosa, which expends its blossoming energies in a 

 burst of glory in May, with foliage almost hidden under 

 a canopy, three or four inches high, formed of umbrellas 

 of tiny pink blooms. This kind forms distinct rosettes 

 and apes the strawberry in its habit of sending out run- 

 ners. The European species most amenable to our condi- 

 tions, if we except the annual, or biennial, A. lactiiiora, 

 IS probably the charming A. carnea. Dwarf, with dark 

 green leaves and flowers of white or pink, it should be in 

 every rock garden where suitable cultural conditions, of 

 well drained soil, porous and peaty, and partial shade, 

 can be given. 



The -Ethionemas are sun lovers, mostly from the 

 coastal regions of Asia ^ilinor and Syria. The best 

 species, although rather tall— about eighteen inches— is 

 A. grandifioruni, which has somewhat glaucous foliage 

 and spikes of rose pink flowers. Of the dwarf kinds, 

 which attain a height of only a few inches, cordifolia and 

 pulchcUum are most desirable. These cannot be classed 

 as alpines, but they are rock plants and really look as 

 though they belong. 



For the present we must omit anv reference to desir- 

 able .species in the genera Anemone. Aquilcgia and 

 Arenaria. and proceed to a consideration of the Campa- 

 nulas. There is an embarassment of riches in this genus, 

 and from a list of about sixty species suitable for the rock 

 garden, it is somewhat flifficult to single out two or three 

 for special mention. The nodding, pale blue bells of 

 t . cccspitosa on slender stems, four to six inches high, 

 should be seen in every alpine garden. It is closely allTed 

 to C. pi(.ulla, of which there are manv garden forms. 

 C. portcnschlagiana, of catalogs, whose blue flowers 

 huddle near its bright green foliage, shows its preferences 

 by hugging the rocks and traveling by means of under- 

 ground stems into every accessible crannv. It is about 

 four inches high. One of the verv distinct Bellflowers is 

 C. pulloidcs, supposed to be a h\brid between C. pulla 

 and one of the carpatica forms. The mixture has en- 

 dowed It with a strong constitution and it is one of the 

 best, and easy to grow. Its foliage forms a mat close to 

 the soil, surmounted by shining blue-purple flowers on 

 six-inch stems. \Ne have raised from seeds and have 

 blossomed in the moraine in Brooklyn, the rare C 

 Allionii. but the plants died after flowe'ring. To get an 

 idea of the appearance of this typical alpine, one should 

 imagine an individual flower of a Canterbury Bell of slaty 

 blue coloring, supported on a stem three inches in length, 

 springing from a tuft of leaves about two inches in diam- 

 eter. 



Of the hardy 



. Pinks there are two that every rock 

 gardener should strive ior—Dianthns alpina, a dwarf 

 species with red flowers spotted with crimson, almost as 

 large as a half-dollar, and D. ncc;lcclus. the Glacier Pink 

 another pygmy, which has bright pink flowers with the 

 undersize of the petals of glistening buft'. Most of 

 Dianthuses are acce])table rock plants^but these two are 

 the best of the genus. 



The genus Linaria contains several plants of interest 

 to the rock gardener but two stand out above the rest. 



J J ■^" "'/"'"'• 's a frail beautv. that deserves all the 



coddling that it usually requires, but the other. L. 



hcpaticccfolia. although it has some pretensions to beauty, 



can only be considered as an execrable weed because of 



(Conlinnrd on page 607) 



