Homerias.—­Beautiful little South African plants.  For out-door cultivation plant the bulbs in a dry, warm situation, from October to January, 3 in. deep, and the same distance apart, in rich, light, well-drained soil, and protect them from heavy rains with a good layer of leaves.  For pot culture put four or five bulbs in a 5-in. pot, place in a cold frame, and cover with cocoa-nut fibre until the growth appears.  Water moderately, and when the flowers fade abstain from supplying moisture.  The bulbs are not quite hardy, therefore they should be removed indoors before frosts appear.

Homogyne Alpina.—­Hardy herbaceous plants flowering in April.  Any soil is suitable for them, and they may be increased by division.  Height, 6 in.

Honesty (Lunaria).—­Interesting hardy biennials.  When dried, the shining seed-pods make a handsome addition to winter bouquets, mixed with ornamental grass.  Any common soil suits them.  Sow the seed any time from April to June, and transplant them to the border in the autumn for flowering the following May.  Height, 1-1/2 ft. to 3 ft.

Honeysuckles.—­These rapid twiners thrive in any loamy soil, and may be increased by putting down layers in the autumn, after the leaves begin to fall.  They can also be propagated by cuttings taken in the autumn and planted in a shady, sheltered spot.  Caprifolium Brachypoda and the evergreen C. Sempervirens are handsome, free-flowering kinds, suitable for almost any situation.  C. Aurea-reticulata has beautifully variegated leaves, which render it very ornamental.  Height, 6 ft. to 8 ft.

Hop.—­A useful hardy climber for covering verandahs, summer-houses, etc.  Plant in rich, loamy soil, and increase by dividing the roots. (See also “Humulus Japonicus.”)

Hordeum Jubatum (Squirrel-tail Grass).—­A very pretty species resembling miniature barley.  Sow seed in March, covering it very lightly, and keep the surface of the soil moist till the grass appears.  Height, 1-1/2 ft.

Horminum Pyrenaicum.—­This hardy perennial produces erect white flowers with blue corolla in June or July.  It will grow in any ordinary soil, but needs protection in winter, as it is apt to be injured by damp.  It may be propagated either by seed or division.  Height, 1-1/2 ft.

Horn Poppy.—­See “Glaucium.”

Horseradish.—­Plant in October or February in deep, rich soil; or it may be grown on a heap of cinder-ashes, or on any light ground through which the roots can make their way readily.  The best way to increase it is by slips taken from the roots.  It requires little or no attention beyond pinching out the tops when running to seed and keeping the ground hoed.