Garden Gossip

with Ted Smith

Today will be the third and final installment in our examination of carnivorous plants. This week I’d like to focus on another plant that is represented right here on Manitoulin Island. The sundews (Drosera sp.) are a genus comprised of nearly 200 species. Drosera is from the Greek drosos meaning dew drops. Sundew plants exist on every continent except Antarctica. They can be found from Alaska to Australia. The Australian sundew family is incredibly diverse with over half the world’s varieties being found there. One group of Australian sundew plants actually produce a tuber which enables them to estivate during the hot dry Australian summers. Another noteworthy sundew grows to over three meters tall.

Sundews are pretty perennial (usually) plants that tend to grow as a rosette of leaves. The leaves of a sundew are pretty spectacular. Each leaf is covered with prehensile stalks. Each stalk is topped by a drop of very sticky liquid that looks just like a tiny drop of dew. When an insect lands on these irresistible drops of liquid they become stuck. Their struggles trigger the plant to wrap them up with first the stalks and then eventually the entire leaf. Once an insect is completely enveloped, digestive juices are released from glands on the leaf. The insect is dissolved into a nutrient rich soup. This soup is then absorbed into the leaf through other glands. Once this action has been completed, the leaf re-opens and the trap is set again. 

The reason sundews need to trap and consume insect prey is that they, just like most other carnivorous plants, inhabit damp swampy areas with acidic nutrient poor soils. This information is critically important for those of us wishing to keep carnivorous plants in our homes. Containers for sundews need to allow for at least twelve centimeters of root depth. The soil needs to be around three quarters long fibre sphagnum or peat moss mixed with one quarter clean sharp sand. Never use regular potting soil for your sundews as the Nitrogen levels will kill your plant. Containers can range from glazed ceramic or plastic pots capable of holding water to full scale terrariums. All the carnivorous plants make incredible terrarium inhabitants as they will embrace the humid conditions to be found there. The soil should be always damp but never water-logged. Daily misting can be quite beneficial but never to the point where you begin to see moulds or mildews forming. Carnivorous plants generally live in conditions where they receive bright light with limited direct contact from hot midday sun. These conditions can be perfectly emulated in east facing windows or, in the case of terariums, with artificial lights. Often, these plants will attract enough insect prey naturally during the summer months, even indoors. One or two feedings a month are generally sufficient. Of course, half the fun to owning these plants is feeding them so do so, but judiciously. Tiny live insects placed directly on a sticky leaf should elicit a visible response. Never put more than three small insects on a leaf and avoid larger prey that may damage the plant trying to extricate itself. Avoid “dead” foods like meat as they can quickly rot and kill your plant. Always cut off any leaves that begin to brown so that the plant does not become susceptible to the rotting process. When watering your carnivorous plants, use rain water or distilled water. If you must use chlorinated tap water, be sure it sits for at least two days first as chlorine can be deadly to these plants. Also avoid well water which is too rich in minerals. In the winter months reduce watering slightly while keeping your sundew cooler and don’t feed them.

When choosing your sundew plant(s), you will have plenty of options. The leaves of these plants can be found in a wide variety of shapes. Some are round while others are long and strap-like. One sundew has an H shaped leaf that is truly odd looking. The flowers of sundews, while not the focal point of growing them, can be quite pretty. If left, these flowers often produce viable seed which can be easily germinated on the surface of warm damp peat or sphagnum moss. The tiny seedlings grow relatively quickly and make great gifts for friends and family. The down side to the flowers is a greatly reduced leaf production during the spring bloom. If you are all about the carnivorous leaves, simply clip the flower stalks off as soon as they appear. While on the topic of growing these plants from seed, please never remove carnivorous plants from the wild. They naturally live in very sensitive environments that can be easily impacted by careless human activity. There are plenty of sources for captive grown carnivorous plants if you take the time to look.

That is the quick look at carnivorous plants. Thanks for coming along and have fun!