July 10, 1909 



H O R T 1 C U^ T^U R E 



39 



other by a devious path, carried over rustic bridges of 

 wood. The whole was very effective at the first, convey- 

 ing a pretty idea, but it is now become greatly over- 

 grown and confused, owing to want of timely thinning 

 out of the multitude of plants originally planted. 



The Gymnogrammas 



These ferns include, from a decorative point of view, 

 some of the most remarkable and interesting plants of 

 the fern family. Probably the commonest of them all 

 is Gymnogranuna sulphurea, and if one is successful in 

 the cultivation of this variety there need be no hesita- 

 tion in growing several of the other kinds. The neces- 

 sary point is to give them stove temperature and as 

 they rapidly become pot bound, plenty of water which 

 should never be allowed to get on the foliage. An ex- 

 ception to the foregoing rule is to be found in Gymno- 

 gramma Japonica (syn. Dietyogramma Japonica) which 

 thrives in an Odontoglossum house temperature, by rea- 

 son of its being neither tomentose or powdery but of a 

 thick glossy leathery texture. Perhaps foremost among 

 the golden powdered varieties capable of forming rapidly 

 large specimen plants is G. calomelanos var. cliryso- 

 phylla ; G. calomelanos is of larger growth but the pow- 

 der is whitish or whitish pink instead of distinctly yel- 

 low. G. calomelanos has a number of forms besides 

 chrysophylla, few of which are of much merit. The 

 principal one, on account of the leaflets turning up thus 

 exposing the powder is G. c. c. Alstoniae. G. e. c. Par- 

 sonsii, named after an old confrere of the writer, should 

 not be forgotten — a crested form not exceeding one foot 

 in the length of its fronds. Am ong the silver or white 

 powdered forms is G. Peruviana, considered to be a form 

 of calomelanos; of which H. B. May's variety Majii is 

 one of the best, having the powder on both sides of the 

 frond and in a lesser degree on the stalks. Another 

 chance seedling is G. Wettenhalliana, golden with very 

 dense crests to its fronds, also having this quality at the 

 tips of its leaflets. G schizophylla is another variety to 

 be found in commercial collections. It makes an ex- 

 cellent basket plant with the remarkable peculiarity of 

 producing plants on its fronds which will freely root 

 when pegged down to a moist surface. G. tartarea is 

 one of the most densely powdered (silver) common in 

 collections. This variety is peculiarly distinct on ac- 

 count of its dark stalks which have no powder upon 

 them. 



The foregoing varieties and forms have been selected 

 not because they are only to be found in herbariums and 

 botanical collections as may be thought by some, but by 

 reason of the fact that they are common with specialists 

 of ferns in Europe and as such are sold commercially on 

 the market. They comprise the best known to cultiva- 

 tion and certainly are worthy of the attention of those 

 who take a pride in the cultivation of choice plants. 

 An additional merit they possess is their adaptability in 

 a dried state for table decoration, retaining the powder 

 and their color for several years; this can easily be ac- 

 complished by drying between sheets of ordinary botan- 

 ical drying paper, with of course a weight on top. In- 

 deed, with a little manipulation, it is by no means diflB- 

 cult to get them into the form of a living plant, a pot, 

 a potato and a little moss forming the necessary 

 material. 



^//0^cv\ s/.</'^^Jyu^nrriC, 



Notes from the Arnold Arboretum 



Isone of the Indigoferas is perfectly hardy in the 

 neighborhood of Boston, but this does not impair their 

 value for our gardens very much, as they, even if killed 

 to the ground during the winter, freely send forth young 

 shoots frtmi the roots in spring which flower profusely 

 the same year. Somewhat hardier seems to be the new 

 Indigofera Eirilowii from Korea but recently intro- 

 duced into cultivation. It resembles very much /. 

 decora aJba cultivated at the Arboretum since many 

 years and tigured in vol. VII on page 375 of Garden 

 and Forest, but has light purple flowers instead of 

 pure white ones. Indigofera Kirilowii is a low bush 

 about one or two feet high with handsome bright green 

 foliage consisting of pinnate leaves with seven to nine 

 roundish leaflets which are rounded at the end and fur- 

 nished with a bristle-like point, not acute as in the 

 other species. The light purple flowers are three- 

 quarters of an inch long and disposed in racemes three 

 to four inches in length which are borne on long and 

 slender stalks in the axils of the leaves and appear dur- 

 ing June and July. It is well worth a place in the 

 borders of shrubberies and could be planted together 

 with the pure white /. decora alba. 



Some time ago attention was drawn in these notes to 

 one of the native Mock-Oranges as the earliest of all to 

 bloom and today a few words may be said about the 

 latest of them. This is Philadelphus californicus — as 

 the name implies, a native of California. It grows 

 into an upright shrub about six feet high or more with 

 bright green rather small foliage and bears at the end 

 of June and beginning of July an abundance of white 

 slightly fragrant flowers. The flowers are compara- 

 tively small, about three-quarters of an inch in 

 diameter, but are borne in rather dense panicles, not in 

 .simple racemes as in most species. As it has proved 

 quite hardy at the Arboretum, it is to be recommended 

 for its late and profusely appearing flowers. 



Another beautiful Mock-Orange which bears the 

 flowers in large panicles and blooms about the same 

 time with P. californicus is PhUadelphiis insignis (P. 

 Souvenir de Billiard or BilUardii). This is probably 

 a hybrid of P. californicus with one of the large- 

 flowered species and is a very showy plant with its 

 panicles of large, pure white flowers. As the finest of 

 our native species I may mention here Philadelphvs 

 inodorus which flowers about two weeks earlier than 

 P. californicus. It is very rare in cultivation ; the plant 

 usually cultivated under this name is P. grandiflorus 

 which also has large flowers, but P. inodorus is much 

 more graceful in habit with its slender arching 

 branches studded their whole length with pure white 

 cup-shaped flowers about two inches in diameter. Of 

 the new Chinese species one of the most distinct is 

 Philadelphus sericanthus, a shrub of spreading habit 

 with distinctly pointed leaves purplish when unfolding; 

 with its horizontal racemes of nodding flowers it re- 

 sembles somewhat a Deutzia of the t'V'pe of D. scdbra 

 (P. crenata) with large but few flowers. It has proved 

 hardy at the Arboretum, but cannot compare in beauty 

 with manv other Mock-Oranges and also apparently 

 none of the otlier new Chinese species will equal, con- 

 sidered from an ornamental point of view, the best of 

 the varieties now in cultivation. 



BrooJcline, Mass. 



