You, possibly, have a plant on your window, called the ivy, in Latin - Hedera helix, i.e. creeping ivy.
Ivy really should not be called "creeping", but "crawling". Its leaves are thick, leathery, dark green, usually palm-shaped. Its stems are long whips.
Let us meet the ivy closer. Turn its stem and leaves upside down. You see, on the other side of the stem, at the bases of the leaves, certain brushes. These are not "legs" that the ivy uses to "walk". They are roots that serve not to supply water and nutrients from the soil, but to move.
They grow beneath the leaf shadow and especially spread out in the dark. The stems of your ivy, which grows in a pot on a window, drape to the sides. Put a branch to the wall thusly that the leaf shadow fell upon it. Of course, not immediately, but after some time the ivy will fasten itself to the wall, at the condition that the wall is damp, and spreading out, it will crawl over it like a millipede.
It can cover not just the window, but also the ceiling and a corner of the room.
How the ivy moves on the wall?
The roots on ivy's stem grow in shadow until they meet a hard obstacle. They penetrate dark cracks and thickening they seal the opening as a cork does. If the wall is smooth, without any cracks, or if they come across glass, then the end of the root thickens like a foot or a palm and produces sticky sap. It is easier to tear the stem than tear it off the wall. The roots at the lower part of the stem gradually firmly attach themselves to the wall; the young roots on the new branches "seek" new places.
Thus the ivy slowly "walks" with its multiple roots. The old roots, who did not find a place to anchor, wither away, sticking out everywhere.
The ivy grows in Crimea, on Caucasus and all over South Europe. It grows in the mountains, rising over sheer cliffs from their shadowy side. The damp walls of old buildings become overgrown with ivy. It grows also in the deciduous forests, climbing tall trees.
The ivy is a shadow-loving plant and it grows well in the woods, enveloping, like a liana, tree trunks.
During ivy's growths one can observe interesting transformations. While the ivy grows in sylvan shadows, its stems, needing anchoring, crawl and drop downwards.
Its leaves are opaque, with five- or seven-point shapes, with a clear angular pattern, with whitish veins.
But as soon as the ivy reaches the top of a tree or a sunlit peak of a cliff, it becomes unrecognizable. Its stems become straight, firm, without any grasping roots. The leaves grow heart-shaped or egg-shaped, shining, with unnoticeable veins. And then, the supposedly never-flowering ivy blooms with greenish-yellow, small, umbrella-shaped flowers.
The flowers with five leaflets, five petals and five pestles smell very strongly. But this smell resembles herring sauce or rotting meat and attracts only flies. The ivy has black berries, but these berries are poisonous.
The ivy blooms when it is eight years old, and it lives up to half a century. Such old ivy has a stem up to a meter in width.
The differences of the shadow part of the ivy and the well lit is seen not only in the external shape of leaves, but also in their chlorophyll content.
The shadow leaves of the ivy (1 kg) contain 3.6 g of chlorophyll, slightly less than as aspidistra does. The lit leaves - only 2.7 g. The shadow leaves are larger than the lit leaves two or three times.
The ivy is a shadow-tolerant plant and thus it grows excellently inside rooms.
Look at the ivy's branches: its entire leaves form one single green plane. All spaces between the large leaves are filled by the smaller ones. The leaves are turned to one another thusly that the edges of their corners almost lock. It is as if all of ivy leaves were set like colored stones in a mosaic. There is a reason why such a position of leaves is called a mosaic of leaves.
Look well at the ivy's leaves. Verily, they got a very beautiful shape? There is a reason why the sculptors and architects decorate balconies and pillars of buildings with ivy leaves made from marble. Ivy leaves are found in ornaments and sketches of garden fences. Ivy leaves decorate the famous Notre Dame cathedral n Paris, built in XIII century.
Pushkin's contemporary, the poet A.I. Podolinsky, dedicated an entire poem to domestic ivy.
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The ivy belongs to the Araliaceae family, and it has a "relative" in Korea - the aralia (Aralia Sieboldi). Wild aralias grow in Siberia too. This very beautiful domestic plant is a tree back in its homeland, which reaches 3-5 m in height. It has shining simple leaves on long stems that are gathered in the upper part of a straight trunk.
In China, one of aralia species are used to make the so-called "rice" paper, drying and pressing together the thin levels of tender white heartwood of the trunk.
In case of another aralia species, all of Mongolian people highly value the root called the ginseng. The domestic aralia, unlike the ivy, grows better at a well-lit window.
It is not very demanding for water, but if it is not watered, then the leaves will drop. Immediately after the watering, almost before your eyes, the leaves go back up.
If one looks closely, the aralia leaves are not identical: the youngest are simple, one-piece; as they age, they develop into two, three, four parts. The eldest may have nine. Make a collection of the form-changing leaves of a growing aralia. Keep in mind that during winter, in a warm room, the aralia sheds its leaves, especially the lower ones. Store it during the winter in a cool space with +8*C temperature.
Aralias may have multicolored leaves too.
It is interesting to bond a multicolored aralia onto a plain one. But the most interesting is to bond the ivy to the aralia and produce a "new plant" - an ivy aralia.