HNCYCLOPHDIA OF GARDENING. 
SPEOIES OULTIVATED: P. nankinensis, leaves bronzy purple, 1 to 3 ft., China; 
nankinensis macrophylla crispa, leaves with crisped edges. : 
Periploca (Silk-vine).—Ord. Asclepiadacee. Hardy deciduous 
twiner. First introduced 1597. 
CULTURE: Soil, ordinary. Position, walls, arbours, summer- 
house or trellises in any aspect. Plant, Oct., Nov., Feb. or March. 
Prune away very weak or old distorted shoots only in March. Apply 
liquid manure occasionally during the flowering season. Propagate by 
cuttings inserted under bell-glass or hand-light outdoors, July to 
Oct.; layering shoots, Sept. or Oct. 
corn CULTIVATED: P. greca, green and brown, July, 10 to 15 ft., S.E. 
Peristeria (Dove-Flower; Dove-Orchid).—Ord. Orchidacez. 
Stove evergreen orchids. First introduced 1826. 
CULTURE: Compost, equal parts loam, leaf-mould, & fine crocks. 
Pot, March or when new growth begins. Position, well-drained pots 
or teak baskets. Water freely April to Sept.; keep nearly dry after- 
wards. Temp., Oct. to April 60° to 65°; April to Oct. 65° to 75°. 
Apply weak stimulants occasionally when plants are growing freely. 
Growing period, March to Oct. Resting period, Oct. to March. 
Flowers appear at base of new pseudo-bulb after resting. Propagate 
by division of pseudo-bulbs, March. 
SPECIES CULTIVATED: P. cerina, yellow, fragrant, summer, Venezuela; elata 
(Dove Orchid), white and purple, fragrant, summer, Central America; Lindenii, 
areal ee purple, spring; pendula, yellow and white, fragrant, summer, British 
Periwinkle.—See Vinca. 
Pernettya (Prickly Heath)—Ord. Ericacew. Hardy evergreen 
Berg heatmne shrubs. First introduced 1825. Berries, crimson, blue: 
black, rose, cream; autumn. 
OUTDOOR CULTURE: Soil, peaty. Position, moist rockeries or 
margins of open or shady shrubberies & beds. Plant, Sept. to Nov., 
or March to Way. 
POT CULTURE: Compost, two parts peat, one part leaf-mould & 
sand. Position, cold or cool greenhouses, or dwelling-rooms. Pot, 
Oct. or Nov. Water moderately. When berries shrivel or fall off, 
plants no further use for pot culture; plant outdoors. 
WINDOW BOXES: Soil, ordinary. Position, sunny or shady. 
Plant, Sept. to Jan. Remove when berries shrivel. Propagate by seeds 
sown }in. deep in bed of peaty soil outdoors in autumn; layering 
shoots in March or April. > 
I EeULeS CULTIVATED: P. mucronata, white, spring, 3 to 6 ft., Magellan 
slands. 
Persea (Avocado or Alligator Pear)—Ord. Laurinee. Stove 
evergreen shrub. Fruit, pear-shaped, purplish when ripe, & edible. 
First introduced 1739. 
CULTURE: Compost, equal parts loam & peat, & a little sand. 
Position, moist stove in pots. Potin March. Water freely in summer, 
little in winter. Syringe daily in spring & summer. Temp., March to 
Sept. 75° to 85°; Sept. to March 55° to 65°. Propagate by seeds sown 
in above compost in a temp. of 85°; by cuttings in sand under bell-glass 
in a similar temperature in spring. 
SPECIES CULTIVATED: P. gratissima, green, summer, 10 ft., W. Indies. 
Persian Cycifamen (Cyclamen persicum).—See Cyclamen. 
Persian Iron-wood (Parottia persica).—See Parottia. 
Persian Lilac (Syringa persica).—See Syringa, 
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