THE DICTIONARY 
OF GARDENING, 
PLOCOGLOTTIS (from plokos, a fold, and glotta, a 
tongue ; referring to a fold in the lip). ORD. Orchideæ. 
A genus comprising eight species of stove, terrestrial 
orchids, with the habit of Eulophia, natives of the 
Malayan Archipelago. Flowers mediocre, shortly pedi- 
cellate, racemose; sepals connate beneath the lip, larger 
than the petals, which are curved at the apex; lip con- 
nate with the column on either side by inflexed, mem- 
branous folds, its limb being convex, undivided, patent, 
at first erect; column free above; anthers two-celled; 
pollinia four, round, with two long, replicate candicles ; 
peduncles or scapes leafless. Leaves ample, membranous, 
plicate. Stem or rhizomes creeping, one or many-leaved, 
not distinctly pseudo-bulbous at base. For culture of 
P. Lowii, the only species introduced, see Cyrto- 
podium. l 
P. Lowii (Low’s). Jl ochre-coloured, spotted with brown, borne 
in a spike on a long, hairy scape. l. cuneate-oblong. udo- 
bulbs obpyriform. rneo, 1865. (R. X. O. 154.) 
PLOCOSTEMMA. Included under Hoya. 
PLÆSSLIA. A synonym of Boswellia. 
PLOUGHMAN’S SPIKENARD. See Baccharis. 
PLUCHEA (so called after N. A. Pluche, who pub- 
lished the “Spectacle de la Nature,” at Paris, in 1732). 
Marsh Fleabane. Syns. Conyza (in part), Gymnema (of 
Rafinesque), Leptogyne, Stylimnus. Including Karelinia. 
Orv. Composite. A genus comprising nearly thirty 
species of greenhouse, tomentose, villous, or sometimes 
glutinous shrubs or sub-shrubs, rarely hardy perennial 
herbs, natives of the warmer regions of America, Africa, 
Asia, and Australia. Flower-heads white, yellow, or lilac, 
heterogamous, in the typical species small, disposed in 
corymbose, leafless, terminal cymes; in a few species, 
larger and solitary at the apices of the branches, or 
rather large and crowded at the tips of leafless 
branches; involucre ovoid, broadly campanulate or sub- 
hemispherical, the bracts few or many-seriate; receptacle 
flat, naked; achenes glabrous or pilose. Leaves alter- 
nate, toothed, or rarely entire or pinnatifid. Few of the 
species are of any horticultural value. P. caspica is of 
very easy culture in the open border, and may be pro- 
pagated by seeds, or by divisions. 
inn oon eg prerane —— — — —— * ne a 
= Borders of Caspian Sea and Siberia. Hardy, herbaceous 
perennial. Syn. Karelinia caspia. 
PLUM. The origin of many of our cultivated Plums 
is quite unknown; several of them, no doubt, have sprung 
from Prunus domestica, but, in all probability, other wild 
- types have contributed. According to some authorities, 
the Sloe, or Blackthorn (P. spinosa), the Bullace (P. 
insititia), and the Wild Plum (P. domestica) are merely 
sub-species, and are united into one species under the 
name of P. communis, which is found in a wild state 
throughout Europe and West Africa. “'The Sloe is con- 
fined to Europe, the Bullace extends to North Africa and 
- the Himalaya” (Hooker). The Plum is a deciduous tree, 
attaining a height of from 15ft. to 20ft., and forming 
a moderately spreading head. From the amount of in- 
formation which is at command regarding Plums, it would 
seem that various sorts were introduced into this country 
from France and Italy during the fifteenth century. The 
fruit has, therefore, been grown from a remote period, and 
the date when its cultivation first began is very uncertain. 
Plums are the hardiest of stone-fruits, and the crop is 
one of the most remunerative, in all favourable seasons, 
from market gardens and cultivated orchards. In private 
establishments, the fruits of all the best varieties are 
much valued for dessert, and those of the coarser and 
less highly-flavoured ones prove invaluable for cooking 
and preserving. For the latter purpose, hundreds of tons 
of the fruit are, in a fayourable season, sent from the | 
surrounding market gardens to London alone. The crop | 
Plum—continued. 
is therefore one of the most important, both for market 
and for private consumption. A fruiting branch is re- 
presented at Fig. 204. 
Propagation. Budding and grafting are the chief 
methods by which varieties of Plums are propagated. 
Young trees may also be readily raised from seeds, and 
from suckers. Suckers are only occasionally used, and 
should never be employed as stocks. The Plum is 
naturally inclined to spread its roots, and throw up 
numerous suckers; and, if these are replanted, or used 
as stocks, the tendency to be constantly throwing up 
other shoots from the base is afterwards apparent. Some 
sorts reproduce themselves nearly true from seeds, as, 
for instance, the Green Gage; but seedlings generally 
vary more or less from the original, and it is, therefore, 
best not to depend on this mode of propagation beyond 
the raising of seedlings as stocks, except, perhaps, with 
Damsons, which may be raised from the stones. Plum 
stocks are required in large numbers for Peaches, Nec- 
tarines, and Apricots, as well as for Plums. The seeds 
Fic. 204. FRUITING BRANCH OF PLUM, 
may be sown when taken from the fruit; or they may 
be stratified, and sown in autumn or early spring. In 
the autumn following, the stocks will be ready for trans- 
planting into nursery lines, preparatory to budding or 
grafting when large enough. For Plum stocks, the 
varieties best snited are the Damson, Mussel, St. 
Julien, and White Pear. The Mussel answers well as 
a stock for standard trees. Shield-budding in July 
and August, and ordinary cleft-grafting in March, 
or just before the sap ceases to flow in September, are the 
most successful methods to adopt. In budding, it is most 
important that wood, and not blossom, buds be inserted; 
and, in grafting, wood-buds, which are sometimes very 
scarce on scions, must be carefully preserved. Stocks for 
grafting must be prepared by being headed-down early 
in the year, before growth begins; and the scions should 
be cut at the same time, or even earlier, and laid with 
their ends in the ground. Attention must specially be 
given to this particular, or a successful union of the parts 
at grafting-time will be out of the question. Standard > 
Plums may be worked near the ground, and the sci 
allowed to make its own stem, or at the proper hei 
