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VARIEGATED, PATTERNED, FANCY-LEAF AND ORNAMENTAL FOLIAGED PELARGONIUMS BY WAYNE HANDLOS, PH.D.
plants produce an amazing array of scented chemicals to delight our noses. But in addition to this, a number of plants produce interesting leaves. In show schedules these plants are usually referred to as “fancy-leaf geraniums.” Personally I have called these plants “variegated leaved geraniums.” Other authors have proposed calling them “ornamental foliaged pelargoniums.” Santa Maria Melosilver
beyond plain green to be found in the leaves of the various species of Pelargonium. The most commonly seen deviation from the all-green leaf is the leaf with a lighter colored or white margin. The cells on the edge of the leaf lack green color due to the absence of the green pigment called chlorophyll. In the absence of green pigment the cells on the edge of Evka L’Elegante the leaf appear white, ivory, cream or yellow in color. Theoretically any leaf can show this
white/yellow pattern have been named. These cultivars include ‘Madame Salleron’, ‘Mrs. J.C. Mappin’, ‘Platinum’, ‘Wilhelm Langguth’ (or ‘Caroline Schmidt’), ‘Frank Headley’, French Lace Mont Blanc’, ‘Mrs. Parker’ and ‘Ben Franklin’ among many others. Variegated P. acetosum The whitish margin is not restricted to the zonal geraniums. Several ivy geraniums have this pattern of variegation and include such cultivars as ‘Evka’, ‘L’Elegante’, ‘Variegated Gay Baby’, ‘Wood’s Surprise’ (or ‘Sunset Marble’). Several of the other species of Pelargonium have this same green/white variegated leaf pattern including ‘Variegated P. acetosum’, ‘Lady Plymouth’, ‘Mint Scented Rose’, ‘Frosted’, ‘Atomic Snowflake’ (these four are forms of the rose-scented geraniums), P. crispum types including ‘Prince Rupert’ (mildly lemon scented), ‘Variegated Prince Rupert’ (or ‘French Lace’) (scentless), ‘Galway Star’ (very lemony).
by) but include the following: ‘Golden Coral’, ‘Lady Love Song’, ‘Miss Australia’, ‘Peach Princess’, ‘Starfire’, ‘Silver Ann’, ‘Princess Virginia’, ‘Love Song’, ‘Golden Princess’, ‘Gilda’ and ‘Cream ‘n Green’ (as listed in the Holt Geraniums catalog). A few angel geraniums have bicolored leaves. They include ‘Ainsbury Beauty’, ‘Rita Rita Scheen Golden Angel Scheen’, ‘Golden Angel’ and ‘Oldbury Duet’.
and ‘Golden Clorinda’. If you look at the examples named above you will see that the width of the white/yellow band varies from a fine line to a band of variable width.
Phyllis Golden Clorinda
the leaf blade. This is referred to as a mottled leaf or “hit or miss variegation”. It is found in some ivy geranium cultivars such as ‘Arctic Frost’; or in ‘Variegated Nutmeg’ or a species- derived cultivar like ‘Dappled Oak’. (Some mottling of leaf color may be due to Arctic Frost viral infections. This normally manifests itself as varying shades of green rather than as Var. nutmeg distinct areas of green or white/yellow.)
darker colored, horseshoe or C-shaped band extending in an arc around the leaf blade (about midway between the edge of the leaf and the base). This darker band in the leaf is found in a number of other species of Pelargonium including P. grandiflorum, P. zonale P. grandiflorum P. mollicomum, P. alchemilloides, P. mutans and P. elongatum. P. mutan
Pelargonium frutetorum has the dark band somewhat closer to the center of the leaf than
does P. zonale. (Several of the cultivars of zonal geraniums (presumably with P. frutetorum in their ancestry) have a dark area covering a high percentage of the leaf blade as in the Pillar series, the Bullseye series or the Black Velvet series. Some collections of P. peltatum (ivy geranium) and some of P. frutetorum Bullseye its cultivars have a dark central blotch at the base of the leaf. Among the scented geraniums, P. panduriforme, P. pseudoglutinosum and their derived hybrids, a dark brown blotch is found ‘Chocolate Peppermint’ show this characteristic. Now to complicate the story still further. If you superimpose the dark band of some zonal geraniums on a bicolored, variegated, green and white/yellow leaf, you will get the very colorful “tricolor” geraniums like ‘Mr. Henry Cox’, ‘Mrs. Pollock’, ‘Dolly Varden’ and ‘Lass O’Gowrie’. The dark band is composed of cells containing a reddish pigment Wildwood Chocolate Peppermint called anthocyanin. This pigment over white cells appears red, over yellowish cells appears orange
leaf depending on its age, cultural factors like temperature, exposure to sun, nutrition etc.) Another interesting pattern seen in some variegated leaves is a reversal of the green and white pattern. In such plants as ‘Freak of Nature’ the margin is green but most of the leaf is white. (This reversal pattern can be
Ivy leaf Lass O’Gowrie Mr.
Henry Cox
found in a number of grasses and the commonly
grown spider plant – Chlorophytum). In cultivars like ‘A Happy Thought’ and ‘Pink Happy Thought’, the white area of the leaf is confined to a smaller portion at the base of the leaf blade and green is the predominant color. Such a pattern is called a “butterfly” leaf pattern. Sometimes the butterfly pattern is a contrast
A Happy Thought Violet Lambton
between shades of green as found in ‘Violet Lambton’.
Some cultivars (especially among the zonals) have yellow-green or chartreuse colored leaves (cf. ‘Persian Queen’) and these are called gold or golden leaved geraniums. If you superimpose Persian Queen Indian Dunes the red band of the zonal type of geranium you get a golden bicolor like ‘Mrs. Quilter’. Or if you superimpose the dark blotch of a frutetorum-type plant you get a cultivar like ‘Indian Dunes’ or ‘Occold Shield’. Lastly – some Pelargonium leaves (primarily among the ivy geraniums but sometimes in zonals) develop a reticulate pattern on the leaf blade. These leaves look like they are cover with a net or mesh. If you examine these leaves closely you will find that the white network follows the veins in the leaf. This pattern can be found in such cultivars as Spotlight Hotline Crocodile ‘Spotlight Hotline’, ‘White Mesh’, ‘Crocetta’ and ‘Crocodile’. This pattern is caused by the presence of a benign virus (vein clearing virus) in the plant. The virus causes the cells over the veins to lack the green color of normal leaf tissue. The virus can be transmitted from one plant to another by grafting an infected (net veined) stem on to an uninfected plant. The virus then moves from the infected plant into the uninfected plant. Therefore any green leafed cultivar can be converted into a variegated, net-veined cultivar without much difficulty. All other characteristics of the plants remain unchanged. The virus in not inheritable from one generation to another and will not be passed on to any seedlings.
The mechanism of other types of leaf variegation mentioned above is much more complicated and will be explained in another article at a later date. But let it be noted that many of the variegated leaves have arisen through mutations (or sports) within the DNA of the plant cells. In some of the variegated plants the arrangement of green and colorless cells is not stable and further changes may occur. The most common of these is the loss of the white cells and the reversion of the leaf to all-green. The all-green shoot should be removed as it is more vigorous and will outgrow the variegated part of the plant. A less common change is the loss of all the green cells and the production of a pure white shoot and/or leaf. Obviously this kind of plant cannot live on its own and will exist only as long as it is attached to the parent plant.
In Victorian times, the multicolor leaf was considered very desirable and a number of cultivars of these plants were grown. Some of the cultivars available today date from the 1800’s. These plants are frequently somewhat delicate and harder to grow than nonvariegated plants. This is due to the fact that they have less chlorophyll and consequently produce less food than the green plants. Less food means less growth. Secondly, many of these plants are not as sun tolerant as the green forms. It is usually suggested that they be grown away from hot, direct sun. If they are in direct, hot sunlight, the leaves may “sunburn” and show some browning of the tissue. Morning sun and afternoon shade are favorable for their best growth. Despite their (sometimes delicate) nature, these are truly a wonderful addition to the great diversity of an already diverse group of plants.
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© 2010, Central Coast Geranium Society (CCGS ) |