An introduction to ivies.
In addition to the English ivy, Hedera helix, there are a number of other species of true ivy. The best known are Hedera colchica, which has a form, `Dentata', that is widely used as a groundcover in hardiness zone 5 and southward. Hedera canariensis, the Algerian or Canary ivy, sometimes known as Hedera algeriensis, it also comes in a variegated form called `Gloire de Marengo'. Hedera rhombea, the Japanese ivy, is native to Japan. Hedera nepalensis, the Nepal ivy, is found in the Himalayas, Afghanistan and western China. Hedera pastuchovii, (Russian Ivy), is an Asiatic species native to the Caucasus Mts. near the Black Sea.
Some plants called ivy are really not ivies at all. The Boston ivy, which is used in northern climates to cover buildings, belongs to the genus Parthenocissus, turns red in the fall and loses its leaves. It is not evergreen. Most of the other plants labeled as ivies are plants of tropical origin and are commonly used as houseplants. This group of so-called ivies includes grape-ivy Cissus rhombifoli, a German ivy Senecio mikanioides, Swedish-ivy Plectranthus oertendahlii, and Kenilworth ivy Cymbalaria muralis. Poison-ivy Rhus toxicodendron is also not a true ivy.
Ivies appear even at casual inspection to be quite variable. There are a number of reasons for this. Not only does ivy appear to easily produce new sprouts of different leaf shape or color, but ivies, (like a number of other plants *,) also have a juvenile stage or form in which overall appearance differs markedly from the adult, or flowering, phase. In the juvenile phase, which is quite prolonged in Hedera, the plant is a vine typically with 5-lobed leaves. Varying numbers of roots are found along the stem, depending on the cultivar, and the conditions. In contrast, the adult plant is bush-like with unlobed, heart-shaped leaves. It bears clusters of inconspicuous green flowers in late summer, followed by blue-black berries the following spring.
Some of the variability seen in ivies is due to ivies' amazing ability to sport or mutate. It is in the juvenile state that ivy easily produces new sprouts that are different from the rest of the plant in size or growth form, shape, or color. It is from these variants that a large number of forms or cultivars have been named, especially in Hedera helix. Thus, unlike the cultivars named in many other groups, Hedera cultivars are not selections resulting from crossing different strains (hybridization), but are sports or mutations that occur in the leaves and stems.
A second factor contributing to ivies' variable appearance is the fact that there is some seasonal variation in the size of the leaves and the length of the leaf stalks, the length and width of the lobes, and the prominence of the veins. When new growth starts, it often occurs as a tremendous growth spurt that produces drastically different-looking leaves. In some cultivars, or in some climates, these changes are hardly noticeable, but in the Bird's Foot ivies with deeply cut foliage, the seasonal difference can be quite pronounced. Of course, such variations will be visible only on pots that are at least several months old.
Lastly, transitional forms in leaf shape occur between the juvenile and adult stages, and some of these forms have been selected and given cultivar names.
The Care Of Ivies
Now that you are the proud owner of a new ivy plant, how do you take care of it? First of all, make sure that the plant has been watered recently. Remove, with a sharp pair of scissors or pruning shears, any branches that may have been damaged in transit. Place the ivy near a window or fluorescent lights, away from cold drafts or hot air ducts. Check the soil moisture daily for the first few days to determine how rapidly the particular plant's soil dries out. Often greenhouse mixes dry out sooner in the home environment than do home potting mixes. If you wait several days before checking your plant, it may already be dried out! Remove all decorative wrapping foil or plastic, or decorative pots before watering, so that the plant is not left standing in a pocket or pot full of water.
Water thoroughly but infrequently. When the soil feels dry, gently add water to the soil until the surface is totally wet and the water drains out of the bottom of the pot. Then do not water again until the soil is almost dry. Do not allow pots to stand continually in water. If the air is dry, raise the humidity surrounding the plants by grouping ivies together on a tray full of wet pebbles or perlite, but do not allow the ivies to stand in water.
Ivies are remarkably tolerant to a wide range of light conditions. But in the home a south or west window can be quite drying especially in summer. A north or east window or filtered or reduced light from a south or west window is satisfactory. Ivies respond well to artificial fluorescent light conditions.
in temperate climates ivies may be summered outdoors in the shade. Never put indoor plants outdoors where they will receive any direct sun.
* Eucalyptus, Boston-ivy Parthenocissus and a number of conifers such as juniper luniperus, Arborvitae Thuia, and Atlantic White Cedar Chamaecyparis--to name a few.
RELATED ARTICLE: Fertilizing.
Since foliage is the main feature of ivies, use fertilizers high in nitrogen (the first number in the fertilizer formulation) to provide good green growth. Apply fertilizer to soil only, since foliar absorption would be minimal, or may even be harmful, under indoor conditions.
In the home, feed actively growing ivies monthly with any foliage houseplant fertilizer, according to the manufacturer's directions. Do not use fertilizer when plants stop growing either in the heat of summer, or when temperatures are cool.
The American Ivy Society is a non-profit organization dedicated to preserving the genus Hedra through education and promotion. AIS members are nurserymen, horticulturists, botanists and plant enthusiasts--professionals and non-professionals who share a passion for ivies of the world. Contact their Web site http.//www.ivy.org
|Printer friendly Cite/link Email Feedback|
|Date:||Jan 1, 2001|
|Previous Article:||Horticulture show countdown: diary of an exhibitor. (Gardening In General).|
|Next Article:||Seedy Saturdays 2001 across Canada.|