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Pelargonium (stork, because the fruit is long and slender like a
stork's bill). Geraniaceae. Geranium of gardens. Pelargonium. Stork's
Bill. Many kinds of pot-plants, popular for indoors and for bedding;
and some of them much planted permanently out-of-doors in California
and elsewhere; flowers showy.
Plants of various habit: some are fleshy and tuberous and are treated
as succulents, but those commonly grown are erect or trailing leafy
herbs or woody below (sometimes shrubby) with sts. somewhat soft and
succulent or small and firm: lvs. mostly opposite, entire to
decompound, stipulate, the foliage often strong- scented: infl.
mostly umbel-like, on axillary peduncles; fls. irregular, the petals
5 (rarely fewer by abortion), the 2 upper usually larger and more
prominently colored, the lower mostly narrow and rarely very small,
the colors pink, red, purple, white, sometimes yellow, often
attractively blotched or veined; calyx 5-parted (or the sepals said
to be connate at base), the uppermost segm. produced at base into a
slender nectar-bearing tube or spur adnate to the pedicel; stamens
10, of which 7 or less are anther-bearing and fertile: fr. of 5
valves, each 1-seeded and separating from the beaklike apex mostly by
coiling and more or less hygro metrically.—Nearly all the
pelargoniums are from S. Afr. All the species mentioned in this
article are from that region, unless otherwise stated. Harvey, in
Vol. I of Harvey & Sender's Flora Capensis (1859-60), admits
163 species; and his descriptions are followed closely in the
characterizations of species given below. Knuth, the most recent
monographer (in Engler's Pflanzen- reich, IV. 129, 1912), admits 232
species and very many well-marked hybrids. Pelargonium is
distinguished from the genus Geranium by technical characters. In
most cases, the fls. of Geranium are regular, but those of
Pelargonium are irregular, the 2 upper petals differing from the
others in size and shape and often in coloring. The most constant
difference between the two genera is the presence in Pelargonium of a
nectar-tube, extending from the base of one of the sepals and
adherent to the side of the calyx-tube or pedicel. This tube is not
seen by the casual observer, but it may be discovered by making a
longitudinal section of the fl. and pedicel.
The person who wishes to study the contemporaneous evolution of
plants may find his heart's desire in Pelargonium. With great numbers
of species and many of them variable and confusing in a wild state,
with plant breeding in many places and continued through two
centuries, and with a large special literature, the genus offers
exceptional advantages and perplexities to the student. Most of the
species early came into cultivation by the English and Dutch, the
South African plants forming at one time almost a separate department
of horticultural knowledge. P. cucullatum, the dominant parent in the
florist's pelargoniums, was known in England as early as 1690. The
two originals of the race of zonal or bedding geraniums were
introduced into England in 1710 and 1714. Early in that century, a
half-dozen species were grown at Eltham, in the famous garden of
James Sherard, and these were pictured in 1732 in Dillenius account
of that garden, "Hortus Elthamensis," a sumptuously illustrated work
in quarto. Even at that time, P. inquinans had varied markedly (see
Fig. 2836).in his "Species Plantarum," 1753, Linnaeus . described the
few species which he knew (about twenty-five) under the genus
Geranium. In 1787, L'Heritier founded the genus Pelargonium, and
transferred many of the Linnaean species. L'Heritier's work
"Geraniplogia," a quarto, appeared in Paris in 1787 to 1788, with
forty-four full- page plates. Recently Kuntze has revived the pre-
Linnaean name Geraniospermum (1736) for this genus, but it is not
likely to find acceptance.
Early in the nineteenth century, many species were in cultivation in
Europe, and experiments in hybridizing and breeding became common.
There appears to have been something like a geranium craze. The
experiments seem to have been confined largely to the development of
the show or fancy pelargoniums, as greenhouse subjects, for bedding
plants had not reached their present popularity. The geranium
interest seems to have culminated in Robert Sweet's noble work on
"Geraniaceae," published in five volumes in London, 1820 to 1830,
containing 500 well-executed colored plates of geraniaceous plants.
At that time many distinct garden hybrids were in cultivation, and to
these Sweet gave Latin botanical names. His fifth volume is devoted
chiefly to garden forms of the show pelargonium type, to which the
general class name Domes- ticum is given in the following sketch. The
development of the zonal or bedding geraniums had begun in Sweet's
time, and he includes them in his pictures, but the larger part of
their evolution is subsequent to his history. Various small works on
pelargonium have appeared. De Jonghe's "Traite Me'thodique de la
Culture du Pelargonium," Brussels, 1844, contains good
bibliographical and cultural data.
Few classes of plants should have more interest to the amateur and
fancier because the species are numerous and varied, the colors
mostly very attractive, the habit of the plant interesting, and the
foliage often with pleasing fragrance; yet, excluding the common
window and bedding geraniums of the P. zonale and P. inquinans type
and the Lady Washington or Show types, they are very little known to
gardeners. A cool greenhouse could be made to yield very interesting
subjects in the species here described and others that may be secured
from collectors in the regions where they grow.
Most of the cultivated forms of pelargonium may be grouped into four
general horticultural classes:
I. The zonal, horseshoe, fish, or bedding types, known to gardeners
as "geraniums." They comprise a mongrel class, designated as the
Hortorum class This race seems to be derived from P. zonale and P.
inquinans. These two species were made by Linnaeus in 1753, but he
founded them on descriptions in earlier works rather than directly on
the plants. In America, the zonal geraniums are very popular, for
they develop their colors well in the bright climate. They are
popular in all countries, however. They probably stand closer to the
lives of a great number of persons than any other ornamental plant.
If a window or a garden can have but one plant, that plant is likely
to be a geranium. The old race of large-flowered and large-clustered
geraniums was known as "nosegay geraniums," because they were
bouquet-like, but this term is not known in America. Another race has
been developed for its zone marked leaves. There is also a race of
double-flowered zonals, which have appeared chiefly since 1860. The
very full double and close-clustered forms lose much of the grace and
charm of the single types. Some of them are little better, to a
sensitive eye, than balls of colored paper. In the development of the
individual flower of the geranium, there have been two ideals—the
English ideal for a circular flower with the petals broadened and
overlapping, and the continental ideal with a somewhat two-lipped
flower and the petals well separated. In the "Gardeners' Chronicle"
in 1841, p. 644, the proper form is set forth in an illustration, and
this is contrasted with the "original form;" the picture is
reproduced, somewhat smaller, in Fig. 2837. "The long, narrow, flimsy
petals of the old varieties," the writing says, "moved by every
breath of wind, and separated to their very base by broad open
spaces, have been succeeded by the beautiful compact flowers of the
present day, with broad stout petals so entirely overlaying each
other as to leave scarcely an indentation in the outline of the
flower; while the coarseness which prevailed in the larger of the old
sorts is replaced by a firmer substance, and a far more delicate
texture." Fig. 2838 shows contrasting ideals, although the picture
does not represent the extremes.
In more recent years a French type has appeared under the name of
"gros bois," or "large-wood" race. It is characterized as follows by
Dauthenay: umbels ordinarily 4 to 5 inches in diameter: flowers very
large; petals roundish, or sometimes triangular, the limb always very
large and giving the corolla a remarkably round contour: leaves very
large, thick and coriaceous, plane or incurved, more or less
indented, strongly nerved, their diameter averaging about 5 inches,
pedicels large and short: peduncles large, rigid, and projecting
beyond the foliage: wood soft, fleshy, very large, often 1 1/2 inches
around. To this type Dauthenay refers the Bruant geraniums, dating
from 1882. A special handbook is devoted to these plants: Dauthenay,
"Les Geraniums," Paris, 1897.
II. The ivy-leaved geraniums, products largely of Pelargonium
peltatum (Fig. 2839). The species is said to have been introduced
into England in 1701. It is a weak and straggling plant, used mostly
in vases, hanging-baskets, and other places in which an overhanging
subject is desired. The foliage is thick and shiny, slightly peltate
and prominently angle-lobed, and the pink or reddish two-lipped
flowers are always admired. Much-improved and double forms are now in
commerce.
III. The "show" or fancy type is known to gardeners as "pelargonium,"
and in this country also as Lady Washington geraniums (Fig. 2845).
These plants are very popular in Europe, being grown in numerous
varieties. They are prominent at the exhibitions. Because of the hot
trying summer climate, these plants are of very secondary importance
in America, although there are many gardeners who succeed well with
them. This race of pelargoniums seems to have descended chiefly from
P. cucullatum, although P. angulosum may be nearly equally concerned
in it. P. grandiflorum is also thought to have been a formative
parent. It is probable that two or three other species are concerned
in the evolution. In fact, the late Shirley Hibbard once wrote (G.C.,
July 3, 1880) that "it must be evident to every cultivator of these
flowers that the blood of a score or so of species is mingled in
them." This marked garden race, which represents no single wild
species, is designated as the Domesticum group.
IV. Various scented-leaved geraniums, known mostly as "rose
geraniums." These are of several species, with then hybrids and
derivatives. The common rose geraniums are nearest P. graveolens and
P. Radula. The nutmeg geranium is P. odoratissimum or P. fragrans.
Aside from the above groups there are several species which appear
sporadically in -the trade, as P. tomen- tosum, P. echinatum, P.
triste, P. quinquevulnerum, P. fulgidum, and P. quercifolium or the
derivatives of them. Few great collections of pelargonium species and
varieties have been made in this country, and this is much to be
regretted.
Culture of zonal geraniums. (C. W. Ward.)
While the general florist may consider geranium- culture the easiest
of all gardening, the fact remains that it is as necessary to observe
the requirements of the geranium as it is to observe the requirements
of any other plant; in order to succeed and produce the best effects
attainable. While it is true that the geranium will grow and make a
good showing with comparatively little care, there is as much
difference between a skilfully grown geranium plant and one
carelessly grown as there is between a fancy and a common rose or
carnation.
To secure the best results it is necessary to propagate from
perfectly healthy stock. The dangers of over- propagation are as
great with the geranium as with most other plants. To keep most
varieties in good health it is necessary to plant the stock intended
for propagation in the field and to propagate either from the
field-grown wood in August or early September, or to lift the plants
in the month of September and plant them on benches in the
greenhouse, where they will become established and will maintain a
vigorous constitution throughout the winter season. The propagation
from field-grown wood is far less successful than from wood grown
inside, and when the field-grown cuttings are placed in sand, a large
percentage of them is likely to damp-off, especially if there has
been a comparatively abundant rainfall in the month of July. The best
method that the writer has found for striking the field- grown
cuttings is to put them in 2-inch pots, using a light sandy soil free
from all manure and chemicals, and to place the pots in the full
sunlight either in a coolhouse or a frame. These cuttings must be
kept on the dry side until the calluses have been well formed,
although they should not be allowed to shrivel at any time. If the
cuttings show signs of shriveling, a light syringing is preferable to
a heavy watering. After the roots have started, the treatment of the
plants is the same as if the cuttings had been rooted in the sand and
repotted. The writer contiders wood grown inside superior to
field-grown wood, as the cuttings are much shorter-jointed; most of
them can be taken from the plant with a heel and 95 to 100 per cent
of them will root in sand in the ordinary cutting-bench.
A good temperature for the geranium propagating- house is 56° to 60°,
with a bottom heat of 65° to 60*. While the cuttings are in the sand
and before they are rooted, care must be taken about keeping them top
moist for fear of "damping-off," or what geranium- growers know as
"black-rot." As soon as the cutting is thoroughly callused and begins
to emit roots, it should be potted up at once. The best soil for
geraniums, according to the writer's experience, is a firm pliable
clay loam; this is best if used absolutely without any manure,
especially fresh manure. After potting the cuttings they should be
lightly watered and shaded for a day or so if the sun is extremely
hot, until the roots take hold and the foliage fills up and the stems
begin to look plump. The geranium should not be grown at any time in
its young state in a soil that is too rich, and care must also be
taken that the plants are not kept too wet.
The geranium is subject to few diseases, and so far as the writer
has been able to observe these diseases are brought on by improper
treatment, such as having too much fresh rank manure in the soil or
keeping the plants too wet. Too much strong plant-food in the earth
combined with too much moisture induces a condition of the leaves
ordinarily called "spot." It usually appears in the hottest weather
or immediately after extreme heat accompanied by copious showers or
rains.
Excellent specimen geranium plants may be grown in pots, especially
of some of the newer French and English round-flowered varieties. In
order to produce the best results, choose young vigorous plants that
have been propagated either in the latter part of August or the
forepart of September, and that have shown a disposition to take hold
immediately, both in rooting and in starting to grow after being
potted. The soil should not be too rich, and it is best to start with
the plant in a rather small pot, say 2 1/2 inches, and proceed onward
with light shifts,—that is, shifting the plant from a 2 1/2-inch to a
3 1/2-inch pot, and so on, letting the sizes increase an inch at each
shift until a 7-, 8-, or 9-inch pot is reached, which will usually be
large enough to flower the finest specimens. Whenever shifting the
geranium, be sure to pot firmly, as a firm soil produces a
short-jointed stocky growth, and far more bloom than a loose or
over-rich soil. When the plants reach a 5- or 6-inch pot they may be
regularly fed with manure- water. The most critical time for these
specimen geraniums will be in the months of July, August, and
September; in these periods exposure to intense sunshine should be
avoided. Too much water and a close temperature are always
detrimental to the geranium. Syringing the foliage frequently to keep
down the temperature is also injurious. If these plants are kept
under glass, a light shading or stripping upon the glass is
beneficial. Probably the best position for such plants in these three
extreme months is on the north side of a row of trees, some distance
away from the trees, where the plants will have the benefit of the
subdued shading of the foliage. If kept under glass and
shaded,abundant ventilation should always be provided. As the winter
approaches, a night temperature of 60° and day temperature of 70° to
75°; with plenty of ventilation in the daytime, especially in bright
weather, seem best to suit the plants. Syringing ruins the flowers,
and too much moisture either in the pot or upon the foliage causes
the spotting of the leaves known as "dropsy." In planting the
geranium in the field or in beds, always avoid an over-rich soil. The
earth should be in good condition and fertile, but must not be loaded
with either chemical or animal fertilizer. Too much water at any
period during the hot weather produces a rank growth, reduces the
quantity of bloom and in most instances induces the spotted foliage
to appear.
Another disease, which is sometimes serious, especially in extremely
hot seasons accompanied with a superabundance of moisture, is
"stem-rot." This frequently attacks imported stock. It is most
serious in intensely hot seasons; the entire plant turns black and
fades and withers away. The stem-rot occurs in varieties that have
been very heavily propagated.
The insects that affect the geranium are also comparatively few. The
red-spider is sometimes a serious pest in summer and is difficult to
get rid of when it is once well established. The only method is to
syringe the plants with an extremely fine spray, and also to pick off
the leaves that are seriously affected and burn them. The green-fly
is also troublesome at times, but is easily managed with the ordinary
fumigation of tobacco. There is a small caterpillar that eats the
foliage and sometimes proves a serious pest. If one can induce a few
ground sparrows or any of the warblers, or even English sparrows, to
make their home about the greenhouse, they will put a speedy end to
these caterpillars. Another remedy is to go over the plants carefully
and to pick the caterpillars off and destroy them. This is tedious,
as it must be done frequently.
In the way of bedding geraniums, as a rule the Bruant section
produces the best results, but there are a number of English and
French varieties that do especially well in our hot climate. The
greatest difficulty in successful geranium-culture in America is the
intense heat of the summer months, chiefly July and August. Some
varieties withstand the heat better than others.
Show pelargoniums. (T. D. Hatfield.)
What are known as show pelargoniums have enjoyed a long popularity.
By the general public, and by old people especially, they are known
as Lady Washington geraniums. They are not so commonly grown as the
so-called geraniums, chiefly on account of their limited season of
bloom and the fact that they cannot endure our hot midsummer suns.
Through the greater part of the summer they are liable to be
neglected. They also require different treatment from geraniums, and
— if skill there be — more skill in cultivation.
At the end of the blooming season, they require rest, — a season of
ripening the growth already made. At this time very little water will
be needed, and they may be stood out in the full sun. Only the old
flower-stems may be removed. In no sense should they be cut back at
this time, neither should water enough be given to encourage new
growth. All the leaves should stay on until they naturally turn
yellow with age, thus securing a thoroughly ripened growth. In
September, one may prune them into shape, sometimes rather severely,
but in any case cut out all weak and soft shoots. They should then be
shaken out and repotted in a light compost, not rich, into the
smallest-sized pots that wil| hold them, for the process of growing
them on has to be gone over every season. After potting, a good
soaking will be necessary, and they may be placed in a well-lighted
coldframe. There is no need to keep them close; the stimulation of
water, and the slight protection of a frame are usually enough to
start them into new growth. No forcing will ever be needed at any
season, and if the grower wished, he might keep them in a cold- frame
until very late in the season, so long as adequate protection against
frost is afforded. They are at their best in May, and to have them in
good condition, one may grow them slowly in a house averaging about
50° night temperature (slightly less in midwinter), from October
onward.
After the turn of the days—in January—repot them, using now a richer
compost. Give a fairly good shift, depending in part on the size of
plants desired, the vigor they show, and the difference in varieties.
If wanted to bloom in April or, as some florists might, at Easter,
they should have been potted at once—in late August or September—into
the size they should bloom in,—a medium size, probably the same as
they had lately occupied, and have been taken indoors to grow on
continuously. But for display in May and June, they are potted again
in January, and some plants may be given another shift when extra
vigor or the possible need of a few extra-large specimens demand it.
They will need careful stopping. Some rubbing out of weak shoots,
when they break abundantly, will help those that remain, and one may
even have to do a little pruning. Stopping, however, must be
discontinued as soon as the flowering stems begin to show, which is
about the end of February in the writer's practice. These stems can
be distinguished easily by a slightly different manner of growth. Up
to this time the plants may be allowed to grow naturally; but if the
gardener wants trained specimens he must begin to bend them as he
wishes them to grow, as their growth speedily hardens and the plant
will readily take and keep the form to which it is shaped.
Water should be given sparingly through the dead of winter. February
and March are the months when the most growth is made, and at this
time one may stimulate them materially by the judicious use of
artificial manures, which may be continued, if necessary, until they
come into bloom. They are much subject to the attacks of green-fly
and red-spider; and as the foliage is fairly tender and liable to
injury from tobacco smoke, reliance must be placed on fluid
insecticides almost wholly. The blooming season is very much
lengthened by giving a slight degree of shade.
The best time to take cuttings is soon after the flowering season.
Often toward the last of the season, the plants make a few "growing"
shoots, and these may be taken; but off and on during the summer one
can get cuttings, and any time until August will do. Cuttings taken
in winter-time with a heel make pretty little plants in 4- or 5-inch
pots without stopping. Cuttings taken at the usual time and grown in
6- or 7- inch pots come in handy in grouping for the front lines. It
is necessary to raise a few plants every season to replace older
plants which have grown too large.
New varieties are raised from seed, which is freely produced. In
hybridizing it does not appear that handpollination has any effect,
as the seedlings seldom show any particular affinity to either
parent.
Index.
anguloeum, 20. filipendulifolium, 1. odoratissimum,
15, 16.
artemisaefolium, 5. fragrans, 16. odoratum, 31.
artemisioides, 5. fulgidum, 3.
pastinacaefolium, 1.
betulinum, 17. glabrum, 7. peltatum, 7,
capitatum, 23. grandiflorum, 8. quercifolium,
25.
clypeatum, 7. graveolens, 26. quinquevulnerum,
2.
cordatum, 18. hederaefolium, 7. Radula, 28.
crispum, 30. hispidum, 27. revolutum, 28.
cucullatum, 19. hortorum, 13. scutatum, 7.
daucifolium, 1 inquinana, 12. Thorncroftii,
10.
denticulatum, 29. lateripes, 7. . tomentosum, 22.
domesticum,21 latifolium,30
transvaelense,10.
Drummondii, 23. laxatum, 1. triste, 1.
echinatum, 14. Limoneum, 31. villosum,1
Endlicherianum, 6. multibracteatum 9. vitifolium, 24.
erectum, 16. multifidum, 28. sonale, 11.
exstipulatum, 4.
I. Lvs. on the pinnate order, although sometimes entire, usually
pinnately lobed or compound. (Nos. 1-5).
Any number of Latin-formed names of Pelargonium may appear in the
trade, for the hybrids and varieties are numerous and not always
readily referable to the species as forms or varieties.—P.
Blandfordianum, Sweet {P. graveolens X P. echinatum). A good grower,
shrubby, the branches roughish pubescent: lvs. flat, 7- lobed, the
lower lobes deeply lobed again, all bluntly toothed, strong-scented:
fls. white or pale blush, the upper petals with 2 red spots. G.M.
54:626.—P. brevipetalum, N. E. Br.=Polycephalum-P.Cotyledonis,L'Her.Lvs evergreen at base of plant, cordate,3in. across,entire or nearly so, whitish beneath wrinkled above:fls on scape-like peduncles above the lvs.2/4 in across, white.
St. Helena. Requires little heat. G. 35:235.—P. inxquilobum. Mast.
Allied to P. multibracteatum. Pilose: lvs. 3-lobed, the terminal lobe
ovate-lanceolate and again lobed in middle, margins toothed: fls.
greenish yellow with purple in base. Trop. Afr. Perhaps same as P.
Fischeri, Engl.—P. luteolum, N. E. Br. A very recent species from S.
Afr.: herb with bulbous root- stock: lvs. 4 or 5, all radical, twice
ternately divided, 1/2-1 1/4 in. long and broad, the ultimate segms.
linear: petals nearly 1/2in. long, pale yellow with 2 red lines at
base.—P. polycephalum, E. Mey. (P. brevipetalum, N. E. Br.), St.
thick and fleshy, ovoid, rising very little above the ground,
short-branched at top: lvs. in a rosette, bipinnately divided,
ovate-oblong in outline, thick and fleshy; pinnae 5 or 6 pairs,
pinnatisect: fls. pale yellow, the petals shorter than sepals. Cape
Colony.—P. roseum, Hort., is a name of no botanical standing, applied
to some of the common forms of rose geranium of the P. Radula group.
L H B
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