.) produce abundance 
2a ere 
DRACOCEPHALUM. 
192 
DRAINING. 
Dovste Dwarr AxLmonp.—See | rich mould, and is propagated by 
Ce’Rasus. 
DovsLe FLOWERS are particularly 
J desirable to cultivate in gardens, not 
only from their beauty, but from the 
comparative certainty that exists of 
their producing their flowers every 
year, the plant not being weakened 
by ripening much seed. This is 
peculiarly the case with the double- 
flowered trees and shrubs; the 
double-flowered Peach, the double- 
flowered Cherry, and the double- 
flowered Hawthorn never failing to 
of blossoms 
every year so long as,the tree con- 
tinues in health ; while the single- 
flowered kinds generally fail in pro- 
ducing an abundant crop of blossoms 
every second or third year. This 
observation does not apply so forcibly 
to semi-double flowers, as they 
generally ripen abundance of seeds. 
Dra'‘sa. — Crucifere.—Whitlow 
grass. Very low plants, admirably 
adapted for rockwork, as they are 
generally found in a wild state in 
the fissures and crevices of rocks 
and mountains. They have white 
or yellow flowers, and should be 
grown in sandy soil, on a bank, or 
in any open situation, exposed to the 
sun. 
Drac#na.-—Asphodelacee.—-The 
Dragon-tree. Eastern trees and 
shrubs with the habit of palms. 
They require a stove in England, 
and to be grown in peat and loam. 
The tooth-brushes called Dragon’s 
root, are made from the root of the 
tree species cut into pieces, about 
four inches long ; each of which is 
beaten at one end with a wooden 
mallet, to split it into fibres. 
Dracoce’puaLum. — Labidte. — 
Dragon’s Head. Several species 
of this genus are well known as 
garden flowers; particularly D. 
Molddavica, the Moldavian Balm, a 
hardy annual, and D. canariénse, 
the Balm of Gilead, a greenhouse 
shrub, which should be grown in 
| 
—————— ceeae ee ne eee ee ee eS eo 
cuttings. Some of the perennial 
species, such as D. canéscens, D. 
grandiflorum (a native of Siberia,) 
and D. austriacum, have large and 
splendid blue flowers ; all these are 
quite hardy in any common garden 
soil, and they are all propagated by 
seeds or division of the roots. 
Drarninc.—Draining in the open 
garden is effected either by surface- 
gutters, into which the water may 
run, which does not sink into the 
soil; or by underground channels, 
formed by earthenware tubes called 
draining-tiles, or by tunnels built of 
brick or stone, or by open drains 
partially filled with small pebbles, 
broken stones or bricks, or even by 
fagots, branches of trees, or other 
similar materials, which will pre- 
serve a porous channel through 
which the water may percolate. 
The draining-tiles or other materials 
should not rise nearer to the surface 
than the common depth of dug 
ground, say about a foot or eighteen 
inches; and they need not be placed 
deeper than the usual depth of 
trenched ground, say between two 
and three feet. Plant-pots and 
boxes are drained by placing crocks 
or potsherds, shells, small stones, 
or cinders, over the hole in the bot- 
tom of the pot; and in large pots 
these materials may be covered 
with any fibrous matter, such as 
old matted roots, loose moss, pieces 
of turf, &c., which will prevent the 
earth from mixing with the pot- 
sherds, stones, or other substances 
employed for draining. The great 
object of draining is to prevent the 
stagnation of water about the roots, 
which rots the spongioles or elastic 
extremities of the fibres, and sod- 
dens or consolidates the earth in 
such a manner that the roots cannot 
penetrate into it, or if they do, that 
they decay for want of air. For 
most plants the best materials are 
old pots, broken into pieces little 
