December 9, 1905 



horticulture: 



Adiantums 



A CUNEATIM SKKUI.INC 



Adianliiiiis are the most useful and most used ferns 

 in decorative work. Tliey arc, in fact, indispensable 

 for this purpose. A. pedatuni is the only one hardy 

 in New England. They require temperate or stove 

 houses according to their origin. Shallow pots, or 

 other pots half-filled with crocks and a mixture of half- 

 decayed leaf mold, loam and a little sand will accom- 

 modate nearly every one. In cultivation they do not 

 like vsun but much light and no sprinkling overhead 

 except in very warm days with plenty of air. 



Some of the deciduous species are specially grown for 

 cutting pui-poses. They are better grown on benches or 

 in boxes; for that use big clumps are not the best. I 

 think it better to let them rest in January and February ; 

 after that clean off all the old fronds, divide the clumps 

 into two to four pieces each and replant in new soil. 

 A. Farleyense in a 10-inch pot will not do much the 

 second year if not separated ; so with others. On those 

 with creeping root stocks it is easy to see that the biggest 

 fronds grow from the extremity of the underground 

 shoots and not from the centre of the clumps; this may 

 be said, with few exceptions, of all other ferns that do 

 not grow from a single stem; naturally that does not 

 include young plants that are to be grown through. 



Adiantum is a genus which includes a great many 

 -pecies. They are all easily recognized by the form of 

 their leaflets which are all more or less heart and wedge 

 shaped, the edges differently dentated or undulated, 

 round or Iqng; the ribs are spread out like a fan from 

 the base toward the edge without midrib; nearly all have 

 thin, black wiry stems. The fruit dots grow at the 

 upper edge of the leaflets in little dots or lines and are 

 recovered by the inverted part of tlie limb which serves as 

 an indusium. As to their usefulness they can be divided 



horticulturally into two sections: first, those that are 

 quick growers and valuable for decoration; second, 

 stove growing species useful mainly for collections. In 

 this latter section are the largest growing and most in- 

 teresting species. 



In the first section is the well-known Adiantum 

 cuneatum. It is a native of Brazil and the easiest to 

 grow, reproducing itself naturally from spores which 

 grow all over pots and benches where a few plants stand 

 in the greenhouse ; it causes trouble sometimes in seeding 

 other fern spores collected near where adiantums stand; 

 the spores being so minute and numerous are blown 

 about and attach themselves to the nearest leaves, and 

 it is not unusual to have a crop of Adiantum cuneatum 

 in the place of wliat was expected. This, and Nephro- 

 dium molle for the same reason, should be kept far 

 from other ferns intended to be used for spore seedlings. 



There are many varieties from cuneatum, all of gar- 

 den origin : A. c. gracillimum is the liest known and 

 very fine ; A. c. Charlotte is not unlike the preceding, 

 finely dentated ; A. c. grandiceps has the top of the frond 

 crested; A. c. Legrandi is a dwarf gracillimum; A. c. 

 Luddemannianum is a very curious plant with its bunch 

 of crested leaflets on top of a naked stem ; A. c. Pecottei 

 is a compact dwarf grower; A. c. mundulum is another 

 dwarf variety. Others are coming to light frequently. 

 A. c. Croweanum is one of the latest. I have one in 

 which the leaflets are all laciniated. Most of these 

 varieties are probably accidental hybrids, taking into 

 consideration the quantity and vitality of A. cuneatum 

 spores. Some are not as fruitful as the type but all re- 

 produce themselves nearly true from spores. 



A. concinnum from West Indies and Central America 

 is another useful plant. The fronds, sometimes two 

 feet long, are symmetrically branched, of a narrow tri- 



A 01 ANTUM TRA l'KZIF< lUM E 



