Jacobaea (_Ragwort_).--May be raised from cuttings in the same way as
Verbenas, and will grow freely from seeds sown in autumn or spring.
It delights in a rich, light soil. The purple Jacobaea is a great
favourite of the public. Flowers in August. Height, 1 ft.
Jacob's Ladder.--_See_ "Polemonium."
Jasione Perennis (_Sheep Scabious_).--A hardy perennial which produces
a profusion of heads of blue flowers in June, and continues to bloom
till August. It enjoys a peat soil, and should have the protection of
a frame during the winter. It can be propagated by seeds, cuttings, or
division. Height, 1 ft.
Jasminum.--These are favourite plants for training over arbours or
trellis-work, and for growing against walls. The hardy kinds will
flourish in ordinary soil. The stove and greenhouse sorts should
be provided with a mixture of sandy peat and loam. They may all be
increased by cuttings of ripened wood planted in a sandy soil under
glass. J. Nudifolium produces an abundance of bright flowers after
its leaves have fallen, and is very suitable for town gardens. J.
Unofficinale is likewise adapted for town, bearing confinement well,
and has very sweet flowers. J. Revolutum needs protection in severe
weather. They bloom in July. Height, 12 ft.
Job's Tears.--_See_ "Coix Lachryma."
Jonquils.--These are quite hardy, and may be grown in the open in the
same manner as Hyacinths. Five or six bulbs in a 5-in. pot make a
very pretty bouquet. They are excellent early flowers, and very
odoriferous. Plant in autumn, placing sand round the bulbs. Best not
disturbed too often. The leaves should not be cut off when withering,
but allowed to die down. They bloom in April. Height, 1 ft.
Joss Flower.--_See_ "Chinese Sacred Narcissus."
Juniper (_Juniperus_).--These useful conifers prefer dry chalk or
sandy soils, but will thrive in any ground that is not too heavy.
J. Japonica, Sabina, and Tamariscifolia do well on steep banks and
rock-work. They may be propagated by seeds, grafting, or by cuttings
of firm young shoots planted in a sandy compost, kept shaded, and
covered with a hand-glass.
K
Kadsura Japonica.--This is a beautiful creeper for a south or west
aspect. It thrives best in loam and sandy peat. Cuttings may be struck
in sand, placed under a glass, and subjected to heat.
Kale.--_See_ "Borecole."
Kalmia Latifolia.--This hardy, dwarf evergreen shrub is deservedly a
great favourite. It produces a wealth of flowers in large clusters. It
requires to be grown in peat or good leaf-mould, and needs pure air.
It is increased by pegging down the lower branches, which soon become
rooted. The flowers are produced from June to August. Height, 2 ft.