Actinella Grandiflora.—­A showy herbaceous plant, bearing large orange-coloured flowers in July.  It is not particular as to soil, and is increased by dividing the roots.  Height, 1 ft.

Actinomeris Squarrosa.—­This hardy and ornamental herbaceous plant bears heads of bright yellow flowers, resembling small sunflowers, from June to August.  It thrives in any loamy soil, and is easily increased by dividing the root.  Height, 4 ft.

Adam’s Needle.—­See “Yucca.”

Adenandra Fragrans.—­An evergreen shrub suitable for the greenhouse.  It thrives best in a mixture of sandy peat and turfy loam.  Cuttings of the young branches stuck in sand will strike.  It flowers in June.  Height, 3 ft.

Adenophora Lilifolia.—­Pretty hardy perennials suitable for the border.  Produce drooping pale blue flowers on branching spikes in July.  Any soil suits them.  They may be grown from seed, but will not allow being divided at the root.  Height, 1 ft.

Adlumia Cirrhosa.—­Interesting hardy climbers.  Will grow in any soil, and are readily increased by seeds sown in a damp situation.  Require the support of stakes.  Bloom in August.  Height, 15 ft.

Adonis Flos.—­Showy crimson summer flowers, requiring only the simplest treatment of hardy annuals.  Sow in March or April in the open border.  Height, 1 ft.

Adonis Pyrenaica.—­A rare but charming Pyrenean perennial species, with thick ornamental foliage, and producing large golden-yellow flowers from May to July.  It needs no special treatment.  Height, 1-1/2 ft.

Adonis Vernalis.—­A favourite hardy perennial, which grows freely from seed in any garden soil.  It may also be increased by dividing the roots.  Height, 1 ft.

AEthionema Cordifolium.—­This little Alpine plant is a hardy evergreen that is very suitable for rock-work, as it will grow in any soil.  Its rose-hued flowers are produced in June.  It may be propagated by seeds or cuttings.  Height, 3 in.

Agapanthus (African Lily).—­This is a noble plant, which succeeds well in the open if placed in a rich, deep, moist loam in a sunny situation or in partial shade.  In pots it requires a strong loamy soil with plenty of manure.  Throughout the summer the pots should stand in pans of water.  Re-pot in March.  Give it plenty of pot room, say a 9-in. pot for each plant.  In winter protect from severe frost, and give but very little water.  The flowers are both lovely and showy, being produced during August in great bunches on stems 3 ft. high.  The plant is nearly hardy.  Several growing together in a large tub produce a fine effect.  It is increased by dividing the root while in a dormant state.

Ageratum.—­Effective half-hardy annual bedding plants, thriving best in a light, rich soil.  Seed should be sown in heat in February or March.  Cuttings root freely under glass.  Height, 1-1/2 ft.  There is a dwarf variety suitable for ribbon borders and edgings.  Height, 6 in.