Venus fly traps (Dionaea muscipula) are fascinating plants. Instead of obtaining all of the nutrients needed for growth from the soil and air like most plants do, these carnivorous plants trap and digest small insects to supplement their nutrient intake. This is due in part to the proclivity of Venus fly traps to live in poor-quality, water-logged soil. Every part of the plant plays an important role in the Venus fly trap's ability to survive.
Venus fly traps have roots that are called rhizomes. These are actually part of the plant's stem that grows horizontally under the ground. Small root "hairs" grow from the bottom of the rhizome, while shoots sprout up from the upper portion of the rhizome. The rhizomes can spread and branch off, forming new plants near the original plant. You will be able to tell individual plants by the fact that Venus flytraps never have more than seven leaves on one plant, according to horticulturists with the American Botanical Society.
The leaves of the Venus flytrap are the first plant parts to appear after the new shoots emerge from the top of the rhizome and break free of the soil. The stems of the leaves are quite short. Many leaves are just above ground level, or even resting on the soil. These wide, flat leaves form the base of the plant and carry out the process of photosynthesis. Depending on the variety of the Venus fly trap, the leaf color can range from green to purple.
The "trapping" part of the Venus fly trap plant is a modified leaf sometimes called a "blade." These trapping leaves are folded in half along something called a "petiole," which works as a hinge, giving the trap the ability to open slowly and close quickly.
The inside of the leaves are covered with small hairs. When the hairs are touched twice, or when two hairs are touched at the same time, the folded leaves will quickly close. The edges of the leaves are lined with "teeth" that interlock when closed, trapping the insects inside. Then, the now-closed, folded leaf will fill with enzymes designed to digest the insect. The opening and closing of the traps can only happen seven times before the leaf will die.
Venus fly traps need to be pollinated to reproduce. In the spring, they send up tall stalks lined with small, white flowers. The stalks are tall so that the flowers will not get caught in the trapping leaves. In addition, insects pollinating the flowers will not be trapped either.