FLOWER OF HELIANTHUS ARGOPHYLLUS.
The genus Helianthus is almost entirely North-American, and for the distinction and limitation of its species we are indebted to the labor of Dr. Asa Gray, now universally recognized as the highest authority on North American plants. In the recently published second part of his "Synoptical Flora of North America" he has described thirty-nine species, six of which are annual. The synonyms and cross-naming adopted by previous authors have led to much confusion, which probably will not now be altogether cleared up, for Dr. Gray warns us that the characters of some of the species are variable, especially in cultivation. It may be added that some at least of the species readily form hybrids. There is always more or less difficulty with a variable genus in making garden plants fit wild specific types, but in the following notes I have described no kinds which I have not myself cultivated, selecting the best forms and giving them the names assigned severally by Dr. Gray to the species to which our garden plants seem to come nearest.
HELIANTHUS ARGOPHYLLUS, SHOWING HABIT OF GROWTH.
Helianthus multiflorus, or, according to Asa Gray, speaking botanically, H. decapetalus hort. var. multiflorus, is mentioned first, because it is the subject of the colored illustration. The name multiflorus is established by long usage, and perhaps was originally given in contrast to the few-flowered habit of H. annuus, for the type of the species is more floriferous than the variety of which Asa Gray says that it is "known only in cultivation from early times, must have been derived from decapetalus," a statement which gardeners would hardly have accepted on less indisputable authority, as they will all think the habit and appearance of the two plants widely different. The variety multiflorus has several forms; the commonest form is double, the disk being filled with ligules much shorter than those of the ray flowers, after the form of many daisy-like composites. In this double form the day flowers are often wanting. It is common also on old plants in poor soils to see double and single flowers from the same root. In the single forms the size of the flowers varies, the difference being due to cultivation as often as to kind.
I have obtained by far the finest flowers by the following treatment: In early spring, when the young shoots are about an inch high, cut some off, each with a portion of young root, and plant them singly in deep rich soil, and a sheltered but not shaded situation. By August each will have made a large bush, branching out from one stalk at the base, with from thirty to forty flowers open at a time, each 5 inches across. The same plants if well dressed produce good flowers the second season, but after that the stalks become crowded, and the flowers degenerate. The same treatment suits most of the perennial sunflowers. The following kinds are mentioned in the order in which they occur in Asa Gray's book:
HELIANTHUS MULTIFLORUS, SHOWING HABIT OF GROWTH.
H. argophyllus (white-leaved, not argyrophyllus, silver-leaved, as written in some catalogues). - An annual with woolly leaves, neater and less coarse than H. annuus, with which it is said soon to degenerate in gardens if grown together with it.
H. annuus. - The well known sunflower in endless varieties, one of the most elegant having pale lemon-colored flowers; these, too, liable to pass into the common type if grown in the same garden.
HELIANTHUS ORGYALIS, SHOWING HABIT OF GROWTH IN AUTUMN.
H. debilis var. cucumerifolius. - I have never seen the typical species, but the variety was introduced a few years ago by Mr. W. Thompson, of Ipswich, from whose seed I have grown it. It becomes 4 feet or 5 feet high, with irregularly toothed deltoid leaves and spotted stalks, making a widely branched bush and bearing well-shaped golden flowers more than 3 inches across, with black disks. It crosses with any perennial sunflower that grows near it, simulating their flowers in an annual form. I had a very fine cross with it and H. annuus, but the flowers of this produced no good seed.
JERUSALEM ARTICHOKE (HELIANTHUS TUBEROSUS).
H. orgyalis (the fathom-high sunflower). - The name is far within the true measure, which is often 9 feet or 10 feet. A very distinct species, increasing very slowly at the root and throwing all its growing efforts upward. The long linear ribbon leaves, often exceeding a foot, spreading in wavy masses round the tall stem, which has a palm-like tuft of them at the summit, are a more ornamental feature than the flowers, which are moderate in size and come late in the axils of the upper leaves.
HELIANTHUS ANNUUS GLOBULUS FISTULOSUS.
H. angustifolius. - A neat and elegant species, which I first raised from seed sent by Mr. W. Thompson, of Ipswich. It has a very branching habit quite from the base like a well-grown bush of the common wallflower. The flowers are abundant, about 2½ inches across, with a black disk. The plant, though a true herb, never comes up in my garden with more than one stalk each year.