136 
LEAF-MOULD FOR EXOTICS. 
very similar to leaf-mould, there is scarcely a departure from nature in the use 
of the latter. 
Another class of plants for which leaf-mould is the fittest of all soils, is the 
beautiful and half-epiphytal genus Mschynanthus. The interesting species of this 
genus will grow in baskets of moss, and even on logs of wood covered with moss ; 
but they are more frequently planted in a compost of heath-soil and loam, and 
treated as pot plants. A few months back, we witnessed two of the species 
cultivated in leaf-mould, and the difference in their aspect, as compared with others 
in the soil above-named and in moss, was striking in the extreme. The leaf- 
mould was evidently the most suitable for promoting luxuriance ; and as it can be 
dried with greater facility in the autumn months — and this is the secret of 
blooming the plants — it must be altogether the most appropriate. What we mean 
by being dried is, such an exposure to the light, and such a partial administration 
of water, that the plants shall just be kept from flagging during July and August ; 
though, perhaps, sufficient exposure in a dry frame will of itself produce the 
desired effect, without any material decrease in the supply of water. 
A tribe closely allied to that just noticed, and demanding very nearly the same 
treatment, will find its type in Columnea Schiediana, splendens^ scandens^ &c. 
These plants, whether grown in baskets for suspending, or ordinarily in pots, 
require abetter soil than heath-mould, and one more open than loam. Leaf-soil is, 
therefore, in all respects, best for them. 
The beautiful race of Ferns, again, so elegant in the forms of their foliage, and 
its lively green hue, and so useful for placing in shady situations, where few other 
plants will thrive, is, from growing naturally in the crevices of rocks, where a 
scanty portion of vegetable mould has been deposited, or beneath dense woods, all 
the surface earth of which is composed of decayed leaves, far from being easy to 
suit as respects a compost. Neither loam nor heath-soil, nor a mixture of both, 
is exactly adapted to them ; and while some perish in one of these, many are 
greatly stunted in the other. Leaf-mould alone is what should be used for them ; 
and that it has not already been the chosen material, is the more surprising, 
because, as we have hinted, they are commonly met with growing in it, or in 
something very like it, spontaneously. 
Until a comparatively recent period, the greatest mistakes have been current 
about the soil most adapted for the Epiphyllous group of Cacti. We allude to all 
the species of Epiphyllum^ and to Cereus flagelUformis and speciosissimus. It has 
been imagined that, in common with the dwarf and round-headed Cactacese, of 
which the species of Echinocactus and Mammillaria are examples, these plants 
would only luxuriate and flower finely in a compost of which brick rubbish consti- 
tuted a principal ingredient. The fact is, however, that some of them are partially 
epiphytal, and that they all need an enriched soil, though they prefer one of a very 
open nature. In place, therefore, of putting them in a sterile earth, or one in 
which much manure exists^ or in moss, we think it would be altogether better to 
