Some plants live in situations where their roots cannot obtain sufficient nutrients, and so they have evolved mechanisms to trao insects and then digest the contests of their bodies. There are three groups of these insectivorous plants – The Fly Traps with spiny-edged leaves which are hinged in the middle, the Sticky-leaved Plants with hairs which secrete insect-catching fluid, and the Pitcher Plants with leaves which are water-filled funnels.
These plants are very difficult to grow indoors – water with rainwater, keep the compost constantly moist and the surrounding air humid, and feed very occasionally with tiny bits of meat or dead flies.
But even if you follow these rules their life span in the average living room will be quite short. Don’t be put off – they will arouse more interest during this limited period than some plants you have had for many years!
Drosera capensis
Types of Insectivores
Fly Traps. Venus Fly Trap or Dionaea muscipula is the most spectacular insectivore in its action. Venus’ Fly Traps gather nutrients from gases in the air and nutrients in the soil. However, they live in poor soil and are healthier if they get nutrients from insects. There is a rosette of heart-shaped leaves, each one fringed with teeth. When touched by an insect the two halves close immediately. When the trap closes over food, the cilia finger-like projections, keep larger insects inside. Fold your hands together lacing your fingers to see what the trap looks like. In a few minutes the trap will shut tightly and form an air-tight seal in order to keep the digestive fluids inside and bacteria out.
Venus Fly Trap
Pitcher Plants. There are two types of Pitcher Plants – the lidded varieties and the hooded ones. Nepenthes coccinea is one of the lidded Pitcher Plants – insects are attracted by the brightly-colored pitcher. Once inside this container they drown in the pepsin solution at the base.
Nepenthes coccinea
There are other lidded Pitcher Plants – Sarracenia drummondii has pale green tubes streaked with purple. Darlingtonia californica is a hooded Pitcher Plant. It’s snake’s-head appearance is responsible for the common name – Cobra Plant. The pale green pitcher will grow to 2 ft or more under ideal conditions – the heavily-veined head and dark forked tongue making this one of the strangest of plants.
Darlingtonia californica
Sticky-leaved Plants. Drosera (Sundew) bears a rosette of leaves covered with red hairs. These hairs secrete the juices which both trap and digest the insects. Drosera binata is an Australian Sundew which bears long and deeply-lobed leaves – the American Drosera capensis has undivided leaves.
