Houseplants Clean Air in Our Homes

I need to purchase some houseplants for my home and office. I am looking for houseplants that will help clean the air. Why? Because research shows that houseplants play an important role in cleaning the air we breathe.

A team of National Aeronautics and Space Administration (NASA) researchers lead by Dr. Bill Wolverton tested the effect of fifteen houseplants on three pollutants known to be present in spacecrafts. 

These same three pollutants--benzene, formaldehyde and trichloroethylene--are present in homes and office buildings. Benzene is a very commonly used solvent that is present in many common items including gasoline, inks, oils, paints, plastics, and rubber. Formaldehyde is a chemical found in virtually all indoor environments, including modern office furniture, grocery bags, and in floor coverings, carpet backings and permanent-press clothes. Trichloroethylene (TCE) is used in printing inks, paints, lacquers, varnishes, and adhesives.

NASA found that certain houseplants removed as much as 87 percent of indoor air pollutants within 24 hours under controlled conditions. Each plant type was placed in sealed, Plexiglas chambers in which chemicals were injected. 

Aglaonema (Chinese Evergreen)

The top plants included Bamboo Palm, Chinese Evergreen (Aglaonema), English Ivy, Gerbera Daisy, Janet Craig Dracaena, Corn Plant Dracaena, Mother-in-Law's Tongue, Pot Mum, Peace Lily, Warneckii, Dracaena, Philodendron, Spider Plant and Golden Pothos. 

Assorted Houseplants

Most effective in removing formaldehyde was the philodrendron, spider plant, and pothos. Flowering plants such as gerbera daisy and chrysanthemums were rated superior in removing benzene from the chamber atmosphere. Other good performers are Dracaena 'Massangeana', Spathiphyllum, and Golden Pothos. "Plants take substances out of the air through the tiny openings in their leaves," Wolverton said. "But research in our laboratories has determined that plant leaves, roots and soil bacteria are all important in removing trace levels of toxic vapors".

 The NASA researchers suggest that for the test plants to be effective "air cleaners" it is necessary to use one potted plant per 100 square feet of home or office space. 

Add houseplants to your home and office. Not only are they nice to look at, but they also make your air cleaner to breathe.

Originally published in Canton Daily Ledger on 2-7-2004 

Houseplant Insects

I recently discovered scale insects on one of my houseplants. They are on my Anthurium (Flamingo Flower) and are causing the leaves to turn yellow and drop off. I know several of you also have an occasional problem with insects on your houseplants. Today I will cover a few of the sucking insects. 

Sucking insects suck the plant’s sugary sap, causing the leaves to turn yellow. Since these insects cannot fully digest all the sugar, they secrete a sticky substance called honeydew. Examples include scale, mealybugs, and aphids. Houseplants infected with these insects will have sticky leaves and sticky areas below the plants. 

Oystershell scale on maple

Scale insects are hard to see. They are brown or gray in color and extremely small. To the untrained eye, they may be unobservable, or you might think they are part of the plant. Upon close examination, you will notice round, oval, or shell-shaped clusters residing upon the branches and stems of infected houseplants. These clusters (scales) can be scraped off the stem. The insects live under this scale, which makes control difficult. 

Scale insects have 3 stages of growth: egg, crawler, and adult. Only the crawlers are easily controlled. Crawlers hatch from eggs and move across the plant. Eventually they lose all their appendages and secrete a waxy covering that forms the observed “shells” which protect the pests. 

Mealybug (in center of picture)

Mealybugs are more obvious. They appear as small, white cottony balls that cluster at the base of leaves. Since they are small, mealybugs hide at the base of leaves and make control difficult. 

Aphids are not as common indoors but do occasionally occur. These also are very small. Aphids are an eighth inch long and come in many different colors: green, pink, red, yellow, brown, or black. In the right situation, aphids build in large numbers, clustering upon new growth and stems. 

For all three of these insects, the control methods are similar. Thoroughly clean plant parts with a cloth dipped in soapy water (for example Ivory or Pine sol). Use 1-2 tablespoons per gallon of water. To get thorough coverage, you might even try spraying the soap solution on with a hand-pump spray bottle. 

In lieu of making your own insecticidal soap, you can purchase them. Commercial insecticidal soaps include fatty materials and smell like grease. Follow all label directions carefully. I do not recommend anything stronger than soap if used in the home. Repeated applications will be necessary. It also sometimes helps to isolate infested plants. 

If the infestation is very bad (and as a last resort), you may need to throw that plant away and purchase a new one. 

Originally published in Canton Daily Ledger on 2-3-2001

Flowering Houseplants: Gerbera Daisy and More

What could be cheerier than a flowering houseplant in your home during the winter? There are different types available ranging from African violets to orchids. 

Gerbera Daisy

Right now, I have a beautiful gerbera daisy blooming in my dining room. Actually, this plant was the centerpiece on my outdoor patio table last summer. I brought it indoors for the winter and it is blooming again. 

Gerbera is a member of the sunflower family. Therefore, it has the typical sunflower look of striking petals surrounding a center. Petals are available in yellow, orange, cream, white, pink or red colors. The center of the flower is sometimes black. 

Gerbera is very popular and widely used as a decorative garden plant or as cut flowers. The plants today are a cross between Gerbera jamesonii and Gerbera viridifolia, resulting in a Gerbera hybrid with thousands of cultivars. They vary greatly in shape and size. Often the same flower can have petals of several different colors.

The big, colorful daisy blooms are on 12-18 inch stems. The plant itself is an 8-12 inch round mass of leaves. 

Gerbera prefer to grow in bright light, warm temperatures, and partly dry soil. It works well outside in our hot, dry summers but be sure to bring it inside before the first frost. Mine grows inside in a southern exposure window. 

Other flowering plants to try indoors include streptocarpus, sinningia, cineraria, primrose, hibiscus, gardenia, cyclamen, and more. Most of these need medium to bright light and good humidity. 

Anthurium

A good option for medium to low light is the anthurium. This tropical plant has unusual, long-lasting flowers in red, pink, and white. The flowers are leaf-like (bracts) with a fleshy spike (spadix) coming from one end. Although they prefer good humidity, they will flower well indoors. Anthurium prefers partially dry soil and is typically planted in a bark-like mix. 

A popular cultivar is Anthurium ‘Lady Jane’. It has slender, clear pink bracts that curve open to reveal long, pink-tipped spadix. It also has glossy dark green leaves. 

Try a flowering plant in your home this winter. They will brighten your day!

Originally published in Canton Daily Ledger on 12-30-2006

Lucky or Curly Bamboo

While on the Spoon River Drive last weekend I (October 2006) came across some curly (or lucky) bamboo for sale. This is a trendy plant that is found many places, including many malls. 

This plant is not a bamboo at all, but the popular houseplant Dracaena. This is a tropical plant native to Southeast Asia or west tropical Africa. You will often find Dracaena growing in dish gardens. 

So how do they transform Dracaena into curly bamboo? As they age, these plants tend to develop long branchless stems with tufts of leaves at the top. Older stems are cut into various lengths and manipulated to twist and turn. Since this plant normally grows straight, growers place the plants in a space with light on only one side. Plants naturally grow toward light. To get them to twist, the plants are manually rotated periodically, forcing a new section to grow toward the light. 

Dracaena (or curly bamboo) is easy to grow. They grow in very low to high light and will grow in soil or water. When growing in water, consistently use one to three inches and change the water every two to three weeks. The plant will produce roots wherever the joints are covered with water. The higher the water level, the more roots it will develop, which can also add to the appearance, particularly in a clear vase. You can also add marbles, river rocks, or polished stones to the container for a decorative touch and to help hold the stalks upright. 

According to Susan Mahr, University of Wisconsin – Madison, the plants can last for years in just plain water. However, Mahr suggests adding a droplet of liquid fertilizer to the water periodically to provide nutrients and help the plant grow more vigorously (supposedly the longer the leaves, the more fortune that is bestowed to you, so fertilizer may really be beneficial!). 

Curly bamboo is used in flower arrangements for unusual interest or alone as special decorations. It has many symbolizations and customs associated with it. It is a centuries old custom to break off a stalk for guests to take home. According to Feng Shui principles, it symbolizes good fortune and is popular during times of celebration. Supposedly three stalks attract happiness, five attract wealth, seven results in good health, and twenty-one stalks offer a very powerful all-purpose blessing. The stalks are often arranged in tiers or tied together in bundles.

Mahr says that lucky bamboo is "recommended by Feng Shui masters and practitioners for improving Feng Shui and creating a space where you feel safe and more energized to meet the demands of today's high-pressured world." Maybe a curly bamboo is just what you need in your home or office to live a better life. 

Originally published in Canton Daily Ledger on 10-21-2006

Clone Your Plants

Do you have an annual flower in your garden this year that you especially like and definitely want to use again next summer? You might be able to clone it using vegetative propagation methods. 

I have a coleus plant that I particularly like in my patio containers. Each fall I take a few cuttings from the plants and grow them in my kitchen windowsill for use next spring. 

If you are an avid gardener, you probably noticed that some plant tags indicate that the plant is patented and thus can’t be propagated. This is true of many of the newer types of coleus. In other words, you can't propagate the patented plant by cuttings or division to sell.

Houseplant cuttings in water and soil

To get started, you’ll need containers, a sterile cutting tool, soil, and a makeshift greenhouse. The container could be anything. I often use disposable cups. Use a good, sterile rooting media that is pre-moistened. I suggest purchasing a premixed potting soil. For best results, create a “greenhouse” for the new plants to grow in until they are well established. I typically use ziplock bags or the little plastic zipper bags that curtains come in. Place your new plant starts in indirect light, opening the bag slightly to provide ventilation without losing humidity inside the bag. 

Division is the easiest way to propagate houseplants that form clumps such as ferns, mother-in-law’s tongue, African violets, spider plants, philodendron, pothos, and more. Simply knock the plant out of its pots and pull the sections apart with your hands. Tough roots sometimes must be cut apart with a kitchen knife. Repot the divisions immediately, add water, and watch your “new” plants grow. 

Cuttings are very simple and can be done several ways. Stem cuttings are taken from the ends of branches. Simply remove 3 or 4 inches of the terminal or end growth just below a node (leaf joint). Some common plants that can be started this way are coleus, geranium, ivy, begonia, and many of the philodendrons.  Simply insert the node of a stem into loose potting soil, water, and watch it grow. 

Want to learn more! Vegetative propagation is an excellent way for hobby gardeners to multiply their favorite plants at home and reap the rewards. Kim Elison, Horticulture Educator, discusses the advantages of propagation in her Four Seasons Gardening YouTube program. She provides detailed insight into various propagation methods including cuttings, grafting, layering and division. 

Consider hosting a plant cloning party this fall. Cloning plants is fun and a great way to share plants among family and friends. 

Originally published in Canton Daily Ledger on 9-26-2015

Bromeliads

My husband Mark and I recently (October 2004) stayed at the Opryland Hotel in Nashville. Opryland is a plant lover’s paradise. It has cascading waterfalls, numerous tropical plants, and many beautiful fountains. 

I spent many hours walking among the tropical plants, reviewing plant names, taking pictures, and simply enjoying the natural beauty. I cannot pick out a favorite, but one bromeliad especially caught my eye.

Bromeliads are in the pineapple family. There are many different types of bromeliads, each with a different exotic look.  They are curvy or straight, large or miniature, dense or light, but all are bold and colorful. Most have brilliant, long-lasting flowers. 

Tillandsia bromeliads are better known as air plants. These grow without soil or added water. You have probably seen them stuffed in little shells and sold as refrigerator magnets. They are also commonly found displayed on driftwood or other small containers. They do required misting and do best in warm, moist areas such as the bathroom or kitchen. Spanish moss is another good example of a Tillandsia. 

The most common bromeliads are the Aechmeas or Urn plants. They hold water in their central cupped leaves. They do require water but can rot if overwatered. They prefer to have their water in their basal leaves to use when they need it. These bromeliads do best in diffused bright light but tolerate some shade. Their flowers grow in colorful clusters above stiff leaves. 

Guzmania in University of Illinois Conservatory

Guzmania are common in many malls and large interiorscapes. These have glossy rosettes of arched, spreading leaves and long-lasting flowers. Guzmania work well in low light conditions. 

Vriesea are the second most commonly grown bromeliad. These are medium size, with soft or firm, variously green but often spotted, blotched or distinctly marked leaves. Flowers are yellow, green or white with brightly colored bracts and may be upright like a spear, pendulous or even curved. 

So which one caught my eye at Opryland? I’m not positive, but it looks a lot like the Aechmea fendleri. It had an impressive brush of lavender-colored flowers on a pink stem dusted with a white bloom. The stem was about a foot tall. Leaves were a large green rosette, with a slight silver tinge. They used the plant in window boxes and in ground beds. 

As you can see, there are many different types of bromeliads. Many make wonderful houseplants and are quite easy to grow. Look for some on your next shopping trip.

Originally published in Canton Daily Ledger on 10-23-2004

Bring Houseplants in Now

I love moving my houseplants outdoors to the porch and patio in the summer. They add peace and beauty to any outdoor room. Unfortunately, they cannot stay there all year. Now is the time to start bringing houseplants in. During the move take the time to groom and clean the plants. And, while you are at it, also consider “fall-cleaning” the plants that remained indoors during the summer. 

Move plants back indoors before nights reach 45 degrees F. Most tropical houseplants are very sensitive to temperature extremes and may show injury symptoms below 45 degrees F. Symptoms of cold injury range from complete leaf collapse to subtle changes in leaf color. 

Clean and groom plants to keep them healthy, clean, and attractive. Also, check each plant to see if it has become root bound. If it is outgrowing its pot, repot it into a bigger pot using a good potting soil mix. Clean plant leaves to remove dust and dirt build-up with 1-teaspoon non-phosphate soap in 1 quart of water. Commonly used soaps include Ivory dish soap and PineSol, but many others are okay too. Use a sponge, cleaning cloth, or paper towel to wipe all surfaces of the leaves clean. Wipe down containers too. Another cleaning option is to spray plants with a non-ammonia glass-cleaning product (such as Sparkle) and wipe clean. Hairy plants should be cleaned only with a brush or feather duster. 

Groom plants by removing debris. Debris found on the plant, on the top of the soil, or at the bottom of the container should be cleaned out regularly. Keep the plant attractive by trimming off old flower heads and all dead or dying leaves. Plants kept outdoors during the summer may need pruning to fit back indoors. Isolate the plants from those already in the house until they are determined to be pest-free. 

Do not despair if some leaves drop after moving the plant indoors. The plant will need to adjust to differences in light levels and watering. Most growing conditions in a home only allow plants to maintain current growth. Some plants, such as Ficus, will adjust to lower light levels by dropping leaves and forming new ones. Others will simply drop lower, older leaves. Water carefully since they will not require as much water as they did outside. The most common mistake homeowners make indoors is watering too much.

Finally, do not fertilize houseplants in the winter. Plants only need fertilizer when they are actively growing. In the winter, most houseplants do not grow much and therefore do not typically need fertilizing. 

Moving nature back indoors for the winter allows homes to come alive. In fact, recent studies indicate that houseplants help keep people happier and healthier. Plants fill an important psychological function and are also proven to cleanse indoor air. Enjoy your plants as you move them in. If you don’t have a houseplant, go buy one. 

Originally published in Canton Daily Ledger on 9-26-1998