Tropicals
General Plant Care
Watering
Proper watering is the most critical factor for the survival of all your plants. The only true way of telling if a plant needs water is by lifting the pot and feeling the weight. If the pot feels light, it needs water, if it feels heavy, do not water. Always use warm water so that you do not shock the plant’s root system. Many plants also benefit from regular misting. Do not mist plants with fuzzy leaves, such as African violets or leaves that are sensitive to water like begonias.
Feeding and fertilizing
Feeding your houseplants should only be done between April and October. Generally, a water soluble 20-20-20 or equivalent organic feed should be sufficient for most plants. Try to feed weekly during the active growing season.
Cleaning your plants
Give your plants a good shower every now and then. Any dust that has collected on them creates an ideal breeding ground for pests. Washing foliage off with a soft warm shower is one of the best things you can do to promote their health. Do not saturate the soil, just wash the foliage (this applies to smooth leafed plants, not to African violets and other flowering plants). Your plants will be clean and fresh, and the moisture will discourage spider mites. It might also be a good idea, while the plants are in the shower, to spray them with a safe, organic pesticide. Safer’s soap products, Origins and other organics will do the job nicely if you keep at it. Preventative organic programs, when used on a regular basis, will prevent most pest problems. They should, however, be applied with a pressure sprayer as the spray must completely cover all parts of the plant, especially the undersides of the leaves, if it is to be effective. Use only warm water when you spray to avoid shocking your plants.
Air Movement
One of the most important, yet often overlooked, way of helping our plants, is to change the air inside our homes. Open the doors and windows, even for a short while, to get some fresh air inside. A fresh supply of air is essential for plants. The movement of air is also critical to prevent mildew and other fungal diseases. With both fresh air and air movement, you will find the atmosphere in your home feels better too.
Transplanting
Mid Spring to early summer is an ideal time to change the pots and soil around our houseplants because they still have a couple of months of good growing weather to settle in before the stressful winter conditions arrive. Now, don’t assume that every plant needs to be repotted. The second cause of plant death, (overwatering being the first), is over potting. Virtually all plants love to be ‘pot-bound’ – in fact, many plants will not grow until the roots have begun to wrap themselves around the inside of a new pot. Ivies are a prime example. Try to get them to grow after transplanting, they simply don’t move until roots have filled their new home.
Transplanting needs to be done carefully, quickly and the new pot should be only slightly larger than the old one. A general rule of thumb is to transplant into a pot two inches larger in diameter than the previous one. Many rootbound plants are sitting in soil which has been drained not only of fertilizers but of organic matter, and many old soils are hard and crusty. Water absorption is minimal because barren soil and massive roots allow little moisture retention. Oxygen, which is so important to a plants survival, cannot penetrate in and around the roots, and without repotting, these plants soon begin to go backwards.
When selecting a pot, the most important consideration is drainage. Many think that plastic pots are not satisfactory. This is not so. Any type of pot is fine as long as it provides good drainage. Clay pots are terrific for most plants because of clay’s ability to breathe and absorb excess moisture. Keep in mind, however, that salt buildup in the soil can discolour clay, leaving a white residue, and algae often forms on the outside. New, easy to apply sprays can prevent both the algae and general guck from messing up your containers. Also, make sure your pots have holes for drainage. Heavy ceramic pots look great, but many of these fancy pots should not be used for growing plants, but should rather be used as container for the growing pot.
The soil you select for repotting should have three qualities: it should be sterilized, contain porosity materials such as perlite or pumice for good drainage, and it must also have moisture retention capabilities. There are many fine soils on the market, but beware of the ones that contain too much sand. You may wish to add a little root booster to encourage fast root development, and weekly feedings of 20-20-20 (or equivalent organic) fertilizer after transplanting will help your plant get re-established.
Before transplanting, make sure your plants are moist. Ripping a dry rootball from a pot will destroy many root hairs and cause set back. If a plant is terribly rootbound soak it in warm water with a little root booster until is stops bubbling, then gently loosen the ball with your hands and ruffle the outside roots. Set the rootball into its new pot, keeping the top of the soil at the same depth as it was before. A serious mistake made by most people is packing the new soil too firmly around the rootball. Simply place the soil around the ball, tapping it gently with your fingers, then tap the pot once or twice to settle the soil in. Let the water do the rest as you puddle the soil in place with thorough drink of warm water.
Newly potted plants should be near an east or north window for a few days to help them become acclimatized, then they are ready to go back to their growing area. Water sparingly after the initial watering. Remember: water well, but let the plants dry out slightly between watering. As the roots develop and take hold, your plant will continue to grow and be well established before winter.
Plants By Light Condition
Bright Light Plants (Receive bright, indirect light for 6+ hours a day)
African violet, Aloe Vera, Asparagus fern, Baby’s Tears, Bridal veil, Bromeliad, Buddhist pine, Cactus/Succulents, Cast Iron plant, China Doll, Chinese Evergreen, Croton, Elephant Ear, False aralia, ferns, Ficus, Anthurium, Jade plant, Sago palm, Jasmine, Kalanchoe, Lipstick plant, Norfolk Pine, Orchids, Peperomia, Philodendron, Pilea, Polka dot plant, Ponytail palm, Prayer plant, Spider plant, Yucca, String of Pearls, Umbrella tree and Zamia.
Moderate Light Plants (Receive bright, indirect light for 4+ hours a day)
Begonias, Calathea, Cycleman, Pothos, Dracaena, Dieffenbachia, English Ivy, Ferns, Grape Ivy, Jasmine, Orchids, Peace Lily, Peperonia, Philodendron, Pilea, Prayer plant, Spider plant, Umbrella tree.
Low Light Plants (North or East facing positions, minimal light)
Buddhist pine, Calathea, Chinese Evergreen, Dracaena, Elephant’s Ear, English Ivy, Ficus, Peace Lily, Pothos, Snake plant, Zamia,
Air Cleaning Plants
Many of our houseplants help to clean the air in our homes and workplaces. It’s no secret that humans would not be able to survive without plants. Thanks to a research study directed by NASA, we now have scientific proof that plants can remove many of the toxins from inside our homes and work areas.
NASA has obviously been concerned about man’s ability to live in closed environments, both on earth and in space. Dr. Wolverton has been the principal investigator in a study on the use of plants to reduce air pollution in confined areas. Twenty common houseplants were tested for their ability to remove from interior environments three of the most commonly recognized pollutants: benzene, trichoroethylene and formaldehyde.
Benzene is a solvent commonly used in inks, oils, paints, plastics and rubber. It has long been known to irritate both the eyes and skin. There is also evidence that it may be a contributing factor in leukemia. Trichloroethylene is a commercial product used in printing inks, paints, lacquers, varnishes and adhesives. The American National Cancer Institute considers it a potent liver carcinogen. Formaldehyde is a chemical found in virtually all indoor environments. It’s used in grocery bags, facial tissues, paper towels and particle board. Many common household cleaning agents contain formaldehyde, as do heating fuels such as natural gas. This chemical can irritate the mucous membranes of the eyes, nose and throat and can cause headaches and irritation to upper respiratory tract.
The plants used in this study were common varieties. They included: Bamboo palm, Chinese Evergreen, Dracaena ‘Janet Craig’, Dracaena ‘Marginata’, Dracaena ‘Warneckii’, Dracaena ‘Massangeana’, Mother-in-law’s Tongue, Peace Lily and Chrysanthemum.
The results were very interesting. When it came to removing trichloroethylene, the Dracaenas, Peace lilies and Bamboo palms scored very well. Chrysanthemums were extremely effective in removing benzene, while the Dracaenas, Bamboo palms, Peace Lilies and Mother-in-law’s Tongue did a fair job.
As for formaldehyde, Bamboo palm did the best, followed by Dracaena ‘Janet Craig’, Mother-in-law’s Tongue and all the rest came in quite a bit lower in the efficiency ratings.
The list of top air cleaning house plants:
- Anthurium
- Bamboo Palm
- Boston Fern
- Chinese Evergreen
- Christmas Cactus
- Chrysanthemum
- Corn Plant
- Croton
- Cyclamen
- Dendrobium Orchid
- Devil’s Ivy
- Dieffenbachia
- Dracaena: Janet Craig, Marginata and Warneckii
- Dwarf Banana
- Elephant Ear
- English Ivy
- Gerbera Daisy
- Heart-leaf Philodrendon
- Lady Palm
- Norfolk Pine
- Peace Lily
- Philodendron
- Prayer Plant
- Rubber Plant
- Snake Plant (Mother-in-law’s Tongue)
- Spider Plant
- Umbrella Tree
- Weeping Fig
For the greatest effectiveness, it is recommended to have approximately one plant for every 100 square feet of floor space.