Growing Carnivorous Plants

By the Plant Information Specialists

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Growing Carnivorous Plants

You can grow carnivorous plants in a variety of conditions, from natural bogs in your backyard to a dish on a windowsill. The trick is to figure out which carnivorous plants will grow well in the conditions you have in and out of your home. Carnivorous plants should never be collected in the field, because most of them are relatively rare and are threatened due to human population, agricultural land use, and over-collection. If you are interested in growing carnivorous plants in your home, purchase the plants from a reputable grower who uses tissue culture or vegetative means to grow the plant, or start them from seeds.

Venus' Flytrap (Dionaea muscipula) South Carolina native

To grow a Venus' flytrap well (and that means still having it alive after 12 months), its natural habitat of the Carolinas must be duplicated. The plant requires an extremely humid and bright sunlit area. It will not grow in freezing temperatures. Water your plant frequently in warm conditions, but do not let it stand in water. To provide warmth and humidity grow your plant in a terrarium.

Keep your plant in the small covered container in which it was purchased. The pot should be about two inches wide and three inches deep. Do not repot your new plant; it should be fine in its current container for about two years or more. Eventually your plant will crowd the pot with numerous side growths on the rhizome. You can then repot, but only in early spring just when it is starting to come out of dormancy.

You do not need to fertilize your Venus’ flytrap, it prefers a lean diet. Do not feed your Venus’ flytrap meat! Live prey, such as such as flies, spiders, crickets, slugs, and caterpillars, are a Venus’ flytrap’s favorite food. No ants, please. Just a note: Caterpillars may eat themselves out of the trap. Do not give a trap any food that is bigger than about 1/3 the size of the trap; larger insects will cause bacterial rot and kill the leaf. When the bug is placed in the trap, the bug’s movement will stimulate the trap into the digestion phase. The plant’s trap may stay closed for a week or less while digesting its dinner.

You can buy crickets for your plant from your local pet store. You can also store frozen crickets and caterpillars in your freezer. During winter dormancy you will not have to feed your plant at all. You will only need to feed your plant about four times per year, one bug feeding at a time. Do not overfeed or your plant may die.

Carnivorous plant color will be green in your home, but with bright light, plants can grow more reddish in color. Venus' flytraps with naturally red color are Dionaea 'Red Dragon', D. 'Red Piranha', and D. 'Colin's Red Sunset.' Dionaea 'Justina Davis' has no red coloration at all, and has a lime-green appearance.

If your plant becomes sickly it probably isn't receiving full sun. It needs bright, full sun, or supplemental lighting, to make it grow healthy and strong. A gently-lit windowsill is too dim for your plant to survive. In a terrarium housing many plants, you may need six fluorescent bulbs placed 12 inches over your Venus' flytraps for vigorous growth.

Sundews (Drosera) 130 species; grow on almost every continent

Many tuberous sundews grow as rosettes of flat leaves pressed against the soil. Fragrant flowers are formed after the leaves have finished growing. The flowers are usually white, and appear in either multiple, single blooms, or are clustered. The curious climbing Drosera can grow many feet, and tiny leaves can stick to other plants with their tentacles. Drosera macrantha is easy to grow from seed. D. macrantha grows to four or five feet and produces one-inch white or pink flowers. The showy bloom cycle appears in winter and spring, and you can keep your plant in a gallon-sized pot for years. Drosera cistiflora is famous for its large flowers. When it is several years old the plant can produce a flower two to three inches across. The flower color can range from purple to rose to white to deep red. Seeds are rarely produced, but you can propagate it by taking cuttings of the early rosetted leaves. A smaller species is D. trinervia with small white flowers. A rare sundew native to South Africa is called King Sundew. It may be a distant relative to the Venus' flytrap. It is large and stiff with sword-like leaves that arch outward in a rosette pattern. The leaves grow to two feet in length, and the roots can develop offshoots. Young plants can move and twist in knots surrounding an unsuspecting prey. The substantial tentacles produce thick globules of mucilage that will overpower large insects. The clustered flowers are deep pink, and one and a half inches across. They take much energy from the plant, so remove them if you want to help your plant. Grow your plant in long-fibered sphagnum moss mixed with one half perlite. D. regia prefers cool, frost-free climates, or grows well in a cool and warm greenhouse. Drosera regia will grow well and large in a big terrarium. Houseflies make a good meal, and a cool, bright environment is a must.

American Pitcher Plant (Sarracenia)

The distinctly shaped pitcher plant is a star in the carnivorous realm. The complex and extravagant pitcher trap functions cleverly. When first discovered, the pitcher plant's shape was believed to function as an unusual water-holding device for droughty conditions. Its carnivorous nature was not suspected. The first description of the pitcher plant was given in 1658 by the French governor of Madagascar, Etienne de Flacourt. The small vase he describes is a leaf that balloons into a hollow, sealed pitcher, and, when mature, develops a popup lid. Glistening nectar and a gaudy pattern on the plant lure insects into the pitcher which holds digestive fluids for unsuspecting victims. Pitcher plants need sandy peaty soil and bright, sunny conditions. Its native habitat, in the southeast coastal plains, is grassy and open, a natural wetland perfect for these types of plants to flourish. The northern purple pitcher plant, Sarracenia purpurea ssp. Purpurea, is the only one found north of Virginia. One species (S. oreophila) and subspecies (S. rubra ssp. Jonesii) are endangered and found in mountains or foothill remnant wetlands above the coastal plain, in northern Alabama. They also grow in places such as the North and South Carolina Piedmont foothills of the Appalachian Mountains.

The second most popular pitcher plant is Sarracenia flava, Yellow Trumpet. The plant can grow to about 20 inches and can mature to 36 inches or more. Unlike S. purpurea’s collar, S. flava’s horizontal lid covers the flared mouth and broad lip, or peristome, keeping out rain. Crawling insects follow nectar trails up the pitcher’s length and become intoxicated. Color patterns lead the prey to the treacherous parts of the leaf, and they eventually fall into the tube. Fluttering insect wings may create a vacuum, causing them to be pulled deeper into the pitcher. The pitcher’s interior is too waxy and smooth for the victim to take foot hold. The plant secretes digestive juice in the deepest inner part of the tube.

There are many species of Sarracenia, such as, S. rubra (Sweet Trumpet), S. rubra ssp. Rubra, S. rubra ssp. Jonesii, S. rubra ssp. Gulfensis, S. rubra ssp. alamensis; S. rubra ssp. wherry. Sarracenia alata (Pale Trumpet) grows in a semi-broken range from Alabama west along the Gulf Coast into eastern Texas.

Sarracenia thrive in one part peat to one part perlite or sand (builder’s sand, not beach sand) mixed together. Long-fibered sphagnum peat is excellent also. Starter four-inch containers made of plastic or glazed ceramics are best. They can be drained or undrained pots. Over time, plants mature in six to eight-inch pots or larger. Keep soil moist to very wet. Most species are happy in warm, temperate climates and are tolerant of light frosts and brief freezes. S. purpurea ssp. purpurea require cold, temperate climates and can tolerate an extended deep freeze in winter.

Mostly sunny to full sun conditions are best for your pitcher plant. Pitcher plants are not candidates for terrariums due to their size and dormancy needs. Native pitcher plants require three to four months of winter dormancy, with reduced temperatures and photoperiod. The most critical element that triggers dormancy in Sarracenia is light. The reduced photo period will induce dormancy in plants, regardless of temperature. Photo periods of 8 to 10 hours in the winter, and 16 to 18 hours in the summer are just fine if you use artificial lighting. However, there is more to dormancy than just light. To ensure a fully dormant plant, temperature and moisture levels should fall as well.

Transplant pitcher plants during dormancy every three to five years.

Sarracenia propagation is by offshoots produced by mature plants. The best producer of many offshoots is Sarracenia rubra. Propagation is best done in winter or early spring. To overcome shock during transplanting use vitamin B1 solution or Superthrive to soak divisions. When placing divisions, place the rhizome horizontally and the roots downward, the growing points should be at the soil surface. Remove any emerging flowers that exhaust the new division.

Butterworts (Pinguicula)

Butterworts are small, herbaceous perennials, wild in Europe, Asia, and in North America. Their method of trapping creatures is by using their leaves, clothed with glandular hairs, to secrete a sticky, dew-like substance. The leaf very slowly rolls over on itself and the glands excrete a ferment. After digestion, the leaf will gradually unfold.

'Pings' have deep pink-purple or lavender flowers, some with white streaking. They number about 70 species and more may be discovered. They grow throughout the Northern Hemisphere from the Arctic Circle down to Siberia, Europe, and North America.

The most popular species to grow is Pinguicula moranensis. It can flourish on your windowsill, and in terrariums and greenhouses. Flowers are usually pink, flowering twice a year, and P. ‘Alba’ is a white form of butterwort. P. moranensis forms vary in leaf shape and size and can flower for many months of the year, before and after summer. P. moranensis ‘G’ is the popular variety that flowers almost continuously throughout the year.

Temperate species require a medium of two parts peat, one part perlite, and one part sand. Warm, temperate varieties need a soil of one part peat to one part sand. Mexican and tropical species require an open mix of equal parts sand, perilite, vermiculite, and peatmoss, with an optional addition of lava rock or pumice. Pots made of plastic or ceramic can accommodate your plant, as long as they have drainage holes. Mexican pings enjoy being grown in calcium-rich abalone shells, and large lava rocks with nook and crannies. The soil can be kept in place with long-fibered sphagnum moss. Hardy varieties are suitable for bog gardens and wet sites in a rock garden that are sunny and humid. They require sandy peaty soil that remains moist. In a greenhouse, just before new growth begins in February, plants are placed in and at the edge of a six inch pot to allow for leaf spread. Do not water from above. Plant pots should be placed in saucers that are always filled with water. In October, when plants are dormant, place them in a room that receives a temperature of 50 degrees at night, and rises only a few degrees higher during the day. Propagation is accomplished by leaf cuttings, a more successful method than seed.

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