BOTANIC THE IMPORTANCE OF INDOOR PLANTS AND THE AIR WE BREATHE
DETOX YOUR DWELLING HOUSEPLANTS DO MORE THAN BEAUTIFY YOUR INDOOR SPACE
VOLUME I, ISSUE I — FALL 2016 Editor, Designer — Sommer BOTANICSmith 1
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Detox your Dwelling— Houseplants do more than just beautify your indoor space. Research shows that keeping plants inside your home can bring a host of physical and mental health benefits. Once you learn more about the therapeutic nature of plants, you’ll be inspired to get your green thumb on.
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House Plants Make You Smarter— You are probably aware that eating plants is good for you. However, what you may not know is that plants can provide benefits even if your taste buds run for cover at the first mention of spinach.
Indoor Gardening— Most avid gardeners don’t check their love of plants at the front door. We keep ferns in the bathroom, begonias in the study, a dwarf citrus in the bedroom, pots of rosemary in the kitchen, and seedlings in the basement. Today there are so
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Planting Healthier Indoor Air— Poor indoor air quality has been linked to health problems, especially in children. Asthma has reached epidemic proportions among multiple age groups and is considered the most common chronic disease in urban-dwelling children. The
American Academy of Allergy, Asthma and Immunology Indoor Allergen Committee suggested in a 2010 report that allergists consider indoor air filtration to be part of a comprehensive strategy to improve respiratory health.
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DETOX YOUR DWELLING
Houseplants do more than just beautify your indoor space. Research shows that keeping plants inside your home can bring a host of physical and mental health benefits. Once you learn more about the therapeutic nature of plants, you’ll be inspired to get your green thumb on.
Plants Fight Pollution Indoors
Indoor air quality is an increasing health concern, particularly in the United States and other developed countries where people may spend up to 90 percent of their time indoors, according to the American Society of Horticultural Science. Indoor air can be as much as 12 times more polluted than Research by the outside air in some areas, National Aeronautics due to compounds in paints, furnishings, clothing, and and Space building materials. Administration Don’t be frightened--get some (NASA) also plants! Research shows that confirmed that plants many common houseplants and blooming potted plants can eliminate harmful improve your health by helping gases from the air. to fight these pollutants in your home. The ability of plants to remove chemicals from the air is called phytoremediation. A study conducted by Stanley J. Kays at the University of Georgia tested 28 species of common houseplants. The results showed that some ornamental plants can remove volatile organic compounds (VOCs) from
indoor air. The purple waffle plant, the English ivy, the variegated wax plant, and the asparagus fern were the top VOCs fighters, according to a study published in HortScience. While it’s common knowledge that plants absorb carbon dioxide and release oxygen as part of photosynthesis, research by the National Aeronautics and Space Administration (NASA) also confirmed that plants eliminate harmful gases from the air. NASA findings showed that houseplants were able to remove up to 87 percent of air toxins in a 24-hour period. Researchers believe that all houseplants may offer these benefits to a certain degree, though they haven’t all been tested. According to this study, the best plants are: dragon tree, ivy, ficus, philodendrons, spider plants, peace lilies, ferns, chrysanthemums, palms, and the rubber plant. You need a plant for every 10 square yards of floor in your house to ensure a considerable degree of air detox.
Plants Help Fight Colds
A study by the University of Agriculture in Norway found that indoor plants can also help fight colds. The research showed that indoor plants decreased coughs, sore throats, fatigue, and other cold-related symptoms by more than 30 percent. Researchers attributed these benefits to the fact that plants help increase humidity levels and decrease dust in your home.
http://www.healthline.com/health/importance-plants-home
Plants Make You Happy
The American Horticultural Therapy Association says that the benefits of plants can be seen across many studies in the cognitive, psychological, social, and physical realms. Some of the psychological benefits include: Increased self-esteem, Improved mood and sense of well-being, Reduced stress, anxiety, and depression, Increased feelings of calm, relaxation, and optimism. Increased sense of stability and control. One area that has been explored is the effect of indoor plants on stress levels. Several independent studies have
shown that interior plants can help reduce stress and improve well-being. A study by researchers at Washington State University found that people in a plant-filled room saw a four-point drop in their systolic blood pressure after taking a stressful test, compared with a two-point drop in a group with no plant The American exposure. Plants Enhance Horticultural Therapy Cognitive Function, Keeping plants indoors can make Association says you think better. The mental that the benefits of benefits observed during this plants can be seen research include: across many studies Improved concentration, Improved memory, Better goal in the cognitive, achievement. Indoor plants psychological, social, have also been linked to a and physical realms. boost in creativity. In a study from Texas A&M University, workers who were in a room with two potted plants and a bouquet of flowers generated 13 percent more ideas than workers in a room with sculptures. Bring more greenery--and less stress--into your home life!
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You are probably aware that eating
plants is good for you. However, what you may not know is that plants can provide benefits even if your taste buds run for cover at the first mention of spinach. New research is beginning to show that just having plants in your workspace may improve how you think. In a study to be published in the Journal of Environmental Psychology, researchers show that the mere presence of plants in an office setting boosts one’s ability to maintain attention. As humans spend more of their lives in front of screens, scientists have devoted more attention to the effects these artificial
environments have on the mind. Sometimes, this new study suggests, it may be possible to reap benefits with simple changes in decorating strategy. These findings build on a body of research based on Attention Restoration Theory. According to this theory, the reason why you can stare at spreadsheets for only so long before wanting to toss your computer monitor through the window is that everyone has a limited capacity for this kind of work. This limited capacity system makes use of “directed attention” which is effortful, controlled voluntarily, and diminishes with use. You can contrast this with the kind of attention that is engaged when you are out walking in a park. Your attention is drawn first to that leaf, then to another. The shadow of a bird streaking across the green grass pulls your eyes along… until a flash of color from flowers by the path grabs your focus. This second kind of attention, called undirected attention, is effortless, automatically oriented to interesting features of our surroundings, and, according to the theory, allows the directed attention system to rest and rejuvenate itself.
Scientists have shown
HOUSE PLANTS MAKE YOU SMARTER
that exposure to naturalistic environments, such as those with much foliage, has regenerative effects for directed attention. However, much of the research in this area has been done with natural scenes on a larger scale – for example, by having participants walk through a park or look at pictures of dense plant life. Research on whether one can still attain the regenerative advantages by simply having a few plants in your workplace has led to mixed results. For example, in one study, participants in a college computer lab with plants showed increased productivity. However, another study failed to find any benefits associated with plants. Still others have found plant-associated benefits only for men, or only for women.
attention demanding tasks: from reading and memorizing at one moment, to writing and recalling at the next. The authors chose this particular measure because the ability to remember and recall information while switching between tasks taps into the “central executive processes” which are thought to be a critical component for directed attention. To test their hypothesis that plants in an office setting would lead to benefits, the authors placed some participants in an office with four plants placed around a desk, and others in the same room without plants. All the participants first took a Reading Span Task to establish a The authors of the present baseline measure study suggest that these Recent research of attention capacity, then a inconsistencies can result from the use proof-reading task, followed suggests that of different tools between labs. Just as by another Reading Span the mere your doctor measures your health in a Task to establish any change number of ways – from taking your blood presence of in their attention capacity. pressure, to determining your body-fat Results of the experiment plants can percentage – so too do psychologists showed that the participants boost your have a number of ways to measure working in the room with attention. Each measurement tool, attention span. plants improved their depending on how exactly it works and performance from the first to which aspect of attention it measures, the second Reading Span Task, while those in may lead to a different result. For this the room without plants did not. experiment, the authors decided to use a Reading Span Task, which involves reading a series of sentences aloud and remembering the last word in each sentence. Similar to the way you might need to remember some information from a spreadsheet before entering it into a word processing document, this task requires that you fluidly switch between
http://www.scientificamerican.com/article/houseplants-make-you-smarter/
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INDOOR GARDENING
Most avid gardeners don’t check their love of plants at the front door. We keep ferns in the bathroom, begonias in the study, a dwarf citrus in the bedroom, pots of rosemary in the kitchen, and seedlings in the basement. Today there are so many interesting plants that can be grown indoors that there’s simply no reason for a gardener not to be surrounded by plants all yearround. Indoor gardening had its first heyday during Victorian times. As plants such as abutilons, palms, and hibiscus were discovered by botanists in remote parts of the world, those who could afford to do so, filled their parlors and conservatories with these exotic beauties. There was another indoor plant revival during the 1970s, though it was largely confined to foliage plants such as spider plants, Swedish ivy, and ferns. Today, commercial greenhouses offer an eye-popping selection of houseplants to choose from, including orchids, bougainvillea, scented geraniums, exotic begonias, pentas, and gardenias. These tropical beauties will bring both color and fragrance to your home. The trick is learning how to keep them happy indoors.
The more you know about your indoor plants and where they come from, the easier it will be to keep them healthy. Understanding a plant’s native habitat can help you decide which potting soil to use, how often to water, what window the plant should be in, and whether or not it needs extra humidity. But even if you don’t have specific cultural information about each and every one of your houseplants, you can feel your way to success with some general guidelines.
are happiest growing in nothing but fir bark or sphagnum moss. A good indoor potting mix is usually composed of peat moss, vermiculite and perlite. These soilless mixes absorb moisture very well and resist compaction, but they tend to dry out very quickly. Since they do not contain any nutrients, you must provide your plants with a consistent supply of fertilizer. One advantage to a soilless A Few Words of Comfort mix is that it is sterile, so there is no Plants have a chance of introducing pest or disease lifespan, just as people problems. Many gardeners add organic do. If you have a struggling houseplant components to their indoor growing mix. that has been around for a few years, These might include leaf mold, finished it may simply be tired, and all the compost, composted TLC in the world may not be able A growing medium peat, or rich garden to revive it. Consider starting over soil. A growing medium with a new plant. Remember that that contains 10 to that contains 10 to 20 unhealthy plants attract insects like 20 percent organic percent organic matter a magnet, and when the infestation matter will usually will usually not dry out spreads to your other plants, you as fast as a soilless mix, not dry out as fast may regret your earlier largeand it also allows you heartedness. as a soilless mix. to introduce beneficial Gift plants, such as cinerarias, microorganisms and poinsettias, chrysanthemums, nutrients. The most critical consideration azaleas and cyclamen, make wonderful when you’re purchasing or blending your indoor decorations, but in most cases own potting soil is to ensure that the they should be discarded after they have mix is light enough to provide adequate finished flowering. Some of these plants pore space for air, water and healthy can be nursed along to flower again, but it root growth. Month after month of is usually difficult to provide the growing overhead watering, without the benefit of conditions they need for another lush earthworms and weather to aerate the soil, display of blooms. usually results in an unhealthy, compacted root zone. To ensure that your plants’ roots The Right Soil have the oxygen they need for healthy If possible, your potting soil should be growth, your potting soil should contain tailored to the particular type of plant plenty of perlite, vermiculite, or sharp you are growing. Cactus, succulents and sand. This will allow water to drain freely, rosemary, for example, prefer a coarse, and ensure that the soil is at least 10 to 20 well-drained soil that is about one-third percent air. sand. Seedlings should be grown in a light, moisture-retentive, soilless mix. African violets and ferns prefer soil with a high humus content, which can be achieved by adding leaf mold or shredded bark. Many kinds of orchids
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Climate, Water and Nutrients
Temperature: In their natural habitat, most plants experience a day-to-night temperature fluctuation of at least 10 degrees F. In your home, they will benefit from having a similar temperature differential. Most plants also expect a resting period each year; in fact, some flowering plants actually require a period of dormancy before they will set bud and flower. To simulate this resting period, you should cut back on water and fertilizer during the late fall and early winter, when the intensity and duration of natural light is lowest. Once the day length begins to increase, you can declare it to be spring, and step up the water and fertilizer. Your plants will respond with healthy new growth. Humidity: Most plants are happiest when the relative humidity is 50 percent or higher, though they can usually survive at 30 to 40 percent. If the air is much drier than that, they are unable to absorb enough water through their roots to keep up with the water lost through their leaves. Unfortunately, indoor air, especially in the winter, often has a humidity as low as 10 to 20 percent.
Misting your plants helps, but only for an hour or so. A better solution is to use a cool vapor humidifier (which you will benefit from as well). You can also cluster your plants together so that, as they release moisture your plants thoroughly before applying into the air, they’ll humidify their any sort of fertilizer. A standard 10-10-10 neighbors. Or try arranging your formulation is fine for most indoor plants. plants on a gravel-filled tray that Supplementing with an organic contains about 1/4 inch of water. As amendment such as liquid seaweed or fish the water evaporates, it will humidify emulsion, or a biostimulant, will provide the air around your plants. Just some of the trace nutrients be careful that the pots don’t sit lacking in an inorganic plant More directly in the water. fertilizer. A top dressing of houseplants Water: More houseplants die compost or worm castings is from overwatering than from die from another effective way to add anything else. The best advice is organic nutrients. Be aware that overwatering to resist the temptation to water some plants are particularly than from on a regular schedule. Your plants sensitive to pH level, and that will require frequent anything else. this sensitivity can be either watering if the exacerbated, or corrected, with weather has been the right fertilizer. To avoid the sunny and warm, and buildup of fertilizer salts, it’s a good idea they may not need a drop to periodically drench the soil with clean if the weather has been cool and water, then water again with clean water. cloudy. Make a habit of checking This will help flush any salts out of the soil. the soil of at least a few indicator plants, and water only if it feels dry to a depth of ½ to 1 inch. When you do water, drench the root ball until you can see some water seep out the bottom of the pot. This will ensure that the entire root ball gets moistened. Small pots will benefit from being soaked in water for about an hour, once a month. Whenever possible, try to water your plants with room temperature water to avoid shocking the roots. Never use water that has been chemically softened. It contains salts that are harmful to plants. If your water is very hard, consider installing a demineralizing attachment to filter out impurities, such as lime and chlorine. Nutrients: Indoor plants are usually not too fussy about fertilizers. The most important thing is to not overdo it. Follow the instructions on the package, and err on the weak side. Always water
http://www.gardeners.com/how-to/indoor-gardening/5079.
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PLANTING HEALTHIER INDOOR AIR
Poor indoor air quality has been linked to health problems, especially in children. Asthma has reached epidemic proportions among multiple age groups and is considered the most common chronic disease in urban-dwelling children. The American Academy of Allergy, Asthma and Immunology Indoor Allergen Committee suggested in a 2010 report that allergists consider indoor air filtration to be part of a comprehensive strategy to improve respiratory health. Air cleaners with HEPA filters have been shown to improve symptoms of asthma.2 However, filtration systems and air purifiers do not reduce levels of all indoor air pollutants, and some types can actually aggravate the problem. For example, one study showed that some air purifiers raise indoor concentrations of ozone above
safety levels established by the U.S. Environmental Protection Agency. A more benign addition to air filtration could be the use of houseplants. In addition to basic photosynthesis that removes carbon dioxide and returns oxygen to the air, plants can remove toxicants from air, soil, and water in at least two ways. First, they can metabolize some toxic chemicals, releasing harmless by-products, and second, they can incorporate toxicants such as heavy metals into plant tissues, thus sequestering them. Data on plant-mediated indoor air quality come from experiments conducted by the U.S. National Aeronautics and Space Administration (NASA). As NASA researchers explored the possibilities of long-term space habitation, it became evident that the air in a tightly sealed space capsule would quickly become contaminated with volatile organic compounds (VOCs) and other chemicals released by the materials used to manufacture the capsule interior. This is similar to the situation in newly constructed energy-efficient dwellings. If energy-efficient construction is not carefully designed to maintain indoor– outdoor air exchange, one unintended consequence can be increased concentrations of pollutants indoors. For
example, in a study recently published in the American Journal of Public Health, Gary Adamkiewicz and colleagues used a simulation model to demonstrate that in homes with low air exchange rates and multiple sources of air pollution, up to 90% of exposure to fine particulate matter came from indoor sources.5 Besides
particles and VOCs, indoor air and dust can also contain brominated flame retardants, pesticides, toxic metals, and other pollutants. For more than 30 years, B.C. “Bill� Wolverton, a retired civilian scientist for NASA, investigated the use of plants as airand water-purifying systems for enclosed environments in space missions. Through his research, Wolverton found the air-cleaning capacity of houseplants can be improved exponentially by increasing air circulation to the roots of the plants, where symbiotic microorganisms help make the substances culled from air bioavailable to the plant. For maximum benefit, multiple species of houseplants would likely be needed on a site to remove the relevant toxicants in a particular space, given that houseplants vary in the types of chemicals they are able
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Removal efficiency based on leaf area of five representative volatile organic compounds (VOCs) [benzene, toluene, octane, trichloroethylene (TCE), and a-pinene] of 28 indoor plants over 6 h during the day.
PLANT
BENZNE
TOLUENE
OCTANE
Superior removal efficiency Hemigraphis alternata Hedera helix Tradescantia pallida Asparagus densiflorus Hoya carnosa
5.54 ± 0.29 3.63 ± 0.33 3.86 ± 0.58 2.65 ± 0.24 2.21 ± 0.21
9.63 ± 0.94 8.25 ± 0.64 9.10 ± 1.17 7.44 ± 0.28 5.81 ± 0.67
5.58 ± 0.68 5.10 ± 0.49 2.76 ± 1.08 3.76 ± 0.64 3.80 ± 0.62
Intermediate removal efficiency Ficus benjamina Polyscias fruticosa Fittonia argyroneura Sansevieria trifasciata Guzmania sp. Anthurium andreanum Schefflera elegantissimaz
1.66 ± 0.07 1.53 ± 0.08 2.74 ± 0.28 1.76 ± 0.48 1.46 ± 0.25 1.31 ± 0.12 0.66 ± 0.19
5.06 ± 0.19 4.29 ± 0.04 5.09 ± 0.23 4.97 ± 0.70 4.04 ± 0.56 3.60 ± 0.37 4.94 ± 0.37
3.98 ± 0.19 3.43 ± 0.08 1.77 ± 0.25 2.73 ± 0.50 2.07 ± 0.24 2.45 ± 0.24 0.65 ± 0.46
Poor removal efficiency Peperomia clusiifolia Chlorophytum comosum Howea belmoreana Spathiphyllum wallisii Schefflera arboricola Codiaeum variegatum Calathea roseopicta Aspidistra elatior Maranta leuconeura Dracaena fragrans Ficus elastica Dieffenbachia seguiney Philodendron scandens ssp. oxycardium Syngonium podophyllum Epipremnum aureumx Pelargonium graveolens
1.20 ± 0.10 0.75 ± 0.11 0.80 ± 0.10 0.75 ± 0.11 0.44 ± 0.07 0.89 ± 0.04 0.94 ± 0.18 0.53 ± 0.08 0.74 ± 0.19 0.55 ± 0.01 0.38 ± 0.07 0.18 ± 0.04 0.49 ± 0.08 0.03 ± 0.02 0.44 ± 0.05 0.03 ± 0.02
2.75 ± 0.11 3.18 ± 0.14 2.95 ± 0.32 2.52 ± 0.13 2.25 ± 0.23 2.28 ± 0.08 2.70 ± 0.38 2.22 ± 0.24 2.67 ± 0.28 2.01 ± 0.08 2.29 ± 0.11 2.03 ± 0.10 1.80 ± 0.11 1.84 ± 0.15 1.54 ± 0.15 1.67 ± 0.29
2.03 ± 0.01 1.70 ± 0.08 1.81 ± 0.28 1.55 ± 0.21 1.75 ± 0.13 1.21 ± 0.03 0.83 ± 0.14 1.22 ± 0.17 0.51 ± 0.19 1.18 ± 0.08 1.20 ± 0.13 1.01 ± 0.10 0.98 ± 0.06 0.76 ± 0.16 0.86 ± 0.09 0.00 ± 0.00
to remove from the environment and the efficiency. In those studies, Wolverton and colleagues tested several types of low-light houseplants. For example, golden pothos (Epipremnum aureum, also known as devil’s ivy) grown on an activated carbon filter system reduced air levels of benzene
tested a small fan-assisted planter/air filter inside a travel trailer that had been used as temporary housing for displaced Hurricane Katrina victims. This trailer, like similar units, had been found to be highly contaminated with formaldehyde. The plant/air filter contained a plant growing in a mixture of activated carbon and expanded clay and trichloroethylene inside a Plexiglas pebbles. Wolverton’s tests showed that the chamber measuring 0.58 cubic yard from levels of formaldehyde were reduced from approximately 36 ppm to barely detectable potentially toxic levels of 0.18 ppm to 0.03 levels within 2 hours.4 Experiments ppm, within the safety limits defined by the conducted elsewhere by Stanley J. Kays World Health Organization. and colleagues at the University of Those studies fit well with evidence on the Georgia also documented the ability biochemical mechanisms involved in plant of different plant species to remove VOCs detoxification of formaldehyde. In studies such as benzene, toluene, octane, and published this year Zhongjun trichloroethylene. Xu and colleagues tested In addition One indoor contaminant of particular three kinds of potted plants to basic concern is formaldehyde, which is photosynthesis, for their capacity to remove released by many household products, formaldehyde from indoor plants can among them pressed woods, some air in test chambers. They remove types of foam insulation, paper found that the formaldehydetoxicants from products, some paints and varnishes, removal capacity of the air, soil, and permanent-press fabrics. The plants depended on the National Toxicology Program lists dehydrogenase activity in and water formaldehyde as reasonably anticipated the leaves and root system— to be a human carcinogen. that is, how efficiently the plant could In an unpublished 2006 study, Wolverton metabolize formaldehyde. As Wolverton found earlier, these investigators also found that formaldehyde removal by plants was diffusion-limited. That means increasing the circulation of contaminated air through the root system and leaves improved the formaldehyde-removal effect.
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3230460/
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