Of the fifty-six species of Inula described in scientific works,
probably not more than thirty are at present in cultivation in
this country, and those are chiefly confined to botanic gardens,
notwithstanding the fact that many of them are useful garden plants.
They are principally distributed throughout Southern Europe, although we
find them extending to Siberia and the Himalayas; indeed, it is to the
Himalayas we are indebted for the kinds that are most ornamental. Some
of the low-growing species are extremely useful for the rockery, such
as I. montana (the Mountain Inula), a fine dwarf plant with woolly
lanceolate leaves and dense heads of orange-colored flowers, resembling
in habit and general appearance some of the creeping Hieraciums. It is a
handsome and desirable plant for the decoration of old walls and similar
places, where it can be a little sheltered from rain and drip. Another
very useful species for this purpose is I. rhizocephaloides, found
plentifully in the Himalayas. It is one of the prettiest Alpine
composites we have. It seldom attains more than from one inch to two
inches in height, forming a dense rosette of short, hairy, oval leaves,
in the center of which the bright purple involucres, in the form of a
ball, are extremely interesting. It is easily cultivated, requiring,
however, a rather snug nook, where it will not be allowed to become too
dry. It is best propagated from seed. Then there is the woolly Inula (I.
candida), a pretty plant with small oval leaves, covered with a thick,
silky down, and much in the way of the white-leaved I. limonifolia, both
of which are very effective when grown in masses, which should always
be low down near the front of a rockery, or as an edging for a mixed
border. The glandular-leaved Inula (I. glandulosa), of which a good
representation is here given, is a beautiful hardy perennial. It is a
native of Georgia and the Caucasian Alps, near the Caspian Sea. It is
a rather robust-growing species, with large, bright, orange-yellow
flowers, varying from three to five inches in diameter, the narrow and
very straggly ray florets contrasting nicely with the rather prominent
disk. The leaves, although quite entire, seem notched, owing to large
black glands which form on their margins. They are lanceolate, and clasp
the stem. The plant is very variable, both as regards robustness and
size of flowers, and this may in a measure account for the confusion
existing between it and I. Oculus-Christi.
The soil most suitable for the full development of I. glandulosa is a
strong, clayey, retentive loam; it does not thrive well in the light
shallow soils in the neighborhood of London, except in shady positions.
I. Hookeri is a free-flowering perennial, with pointed lanceolate
leaves, of a delicate texture, bright green, and very finely toothed.
The flowers, which are sweet-scented, are not so large as those of I.
glandulosa, and are produced singly, the ray florets being, however,
much more numerous, rarely numbering less than thirty. It is found in
abundance in rocky places in Sikkim, where it replaces the nearly allied
I. grandiflora, a dwarfer species, with much shorter, shining leaves;
both are very desirable plants either for rockery or flower border work.
The Elecampane (I. Helenium) is an imposing, robust-growing species,
having large, broad leaves a foot or more in length. It grows from four
feet to five feet in height, and its thick, shaggy branches are crowned
with large yellow flowers. For isolating in woods this plant, is very
useful, and with the exception of Telekia cordifolia, it would be hard
to find a rival to it. It is, I believe, pretty extensively used for
planting in shrubberies, but unless they are thin and open it is seldom
seen to advantage. It is found wild or naturalized in some parts of
England. It flowers in June and July, and even into August when the
season has been favorable.
[Illustration: INULA GLANDULOSA (_flowers deep yellow_.)]
For naturalizing in woods the following will be found useful, _viz_., I.
salicina, I. Oculus-Christi, I. squarrosa, I. britannica, and many more,
the true beauty of which can only be realized in this way. With the
exception of I. rhizocepbaloides, they are all propagated by division
with the greatest ease, or by seed, which is best sown as soon as it is
ripe.--_D.K., The Garden_.
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