Houseplants: The Essentials For Growth
The Essentials For Growth
All plants must have certain things to grow well. In previous articles I have explained the basic needs of plants in a garden environment, but not in the environment of a house or building. The essentials, though, are the same: light (including the length of the day and night hours), heat (temperature), water (including humidity), nutrients, a suitable medium in which to grow, and protection from insects and diseases.
Though house plants have the same basic requirements, the gardener must remember at all times that these plants are not in their natural environment. They have been taken suddenly from a most cooperative growing area to one which is less cooperative, even hostile.
The following inhibiting conditions must constantly be reckoned with in indoor gardening:
- The low light intensity of many rooms in our homes
- The low humidity when the furnace or air conditioner is operating compared with the growing area of the plant in its natural state
- The variable number of light and dark house in our seasons, compared with the almost even number of light and dark hours in the tropics.
Furthermore, growing plants successfully indoors involves attention to:
- Providing a better environment than that normally found inside modern buildings
- Choosing the best plants for any set of conditions indoors
- Adapting outside growing practices to fit the restricted soil area provided by pots or planters
- Altering set practices during the transition periods in spring, when the heat is turned off and the air conditioning is turned on, and in the fall, when the air conditioning is turned off and the heat is turned on.
The Best Environment
The first essential to provide for indoor plants is higher humidity. Most of the year the air in our homes and buildings very dry. Lately it has been suggested that this dry air is not as healthy for us as we previously thought; many doctors now recommend humidifying the air which passes through the central heating system. This helps plants to a certain degree, but even the humidifier on a furnace does not raise the relative humidity in a building as high as it was in the native habitats of most house plants. One of the best helps I have found is a simple cold-air vaporizer. If you will place one of these vaporizers among groups of house plants, you will be surprised how quickly their growth improves.
There are other satisfactory methods of raising the humidity. Spraying the plant’s foliage with a fine mist of fresh water once or twice a day will help, especially during the transition periods from heating to air conditioning. When you set pots in groups, try placing them on gravel in a watertight pan. Fill the pan with water about halfway up the gravel. Do not allow the post, however, to sit in water.
Do not place pants near an open heat vent or in the stream of air from an air conditioner. The drying effect from either source will make your plants suffer badly.
The second essential to provide for indoor plants is more light. Try taking your camera into a shady area outdoors which you think is similar to the light conditions inside your building. Make the proper adjustments to take a good picture. Then go inside and, without changing the speed setting, see what f-stop is required to take the same type picture there. If the setting is a lower number, you will know that the light inside is leass than what you considered equal light conditions outside. This simple test helps prove how dark it really is inside a building.
Artificial light can help plants grow and should be used when light conditions inside are extremely bad. However, use the camera test when adding artificial light so that you can give the plants the amount they need.
The best answer to the light intensity problem is to use natural sunlight through windows. Plants will grow well when placed in sunny areas indoors. Use the camera test here, also. When taking the reading inside, however, do not point the camera at the window; instead, stand in front of the window and point it toward the area where you will place the plants.
Some precautions should be followed when plants are placed in direct sunshine:
- Use only plants that need bright light.
- Watch your watering schedule. When the sun’s rays fall directly on the soil surface of the pot, the planting medium will dry through rapid surface evaporation as well as the normal transpiration from the leaves.
- Be careful when placing plants next to a window in the winter because heat radiation from the leaves to a cold sky may reduce the leaf-surface temperature to a dangerously low level.
There are other ways of improving a building’s light to allow you to grow better plants. Overhead skylights brighten an area tremendously. Window greenhouses are helpful additions to any room, providing a fine environment for many plants that do poorly under normal house conditions as a part of their buildings.
I built a free-standing greenhouse in my yard many years ago, and use it as a hospital for ailing plants which have suffered under my household conditions, as well as a growing house for blooming plants to bring inside our home on special occasions.
Plant Selection
There is an almost limitless number of house plant types which are being propagated for growing indoors. Whether green plants, colorful leaf plants, or flowering plants, the choice is yours. You can be successful with them all, provided you try to grow them with the inhibiting factors I have mentioned in mind.
Choosing which house plants to buy is like landscaping you home or beginning a garden. You have two ways to approach the problem:
- You can choose plants which fit the cultural situation of a particular spot in your building. If the light is low, find a plant with a very low light requirement. If the room is cool, find a plant which grows well in low temperatures.
- Or you can choose a plant which completes the decorative look of the area and then adjust conditions to help it grow well. Perhaps a palm is ideal for a spot where you need height but there is too little light. One answer is to use enough artificial light to satisfy the needs of the plant.
The important point to remember is that a dying or poorly growing plant will detract from rather than add to the beauty of a room. The plant list section of this area will guide you as you begin making your choices.
Healthy Growing Practices
I have stated that all plants which are grown indoors are natural in another place and another environment. All grow in the ground, with the exception of a few which have adapted themselves to growing in trees. None are ever native to a pot or planter, just as none are native to the inside of a building.
To be successful you must start with a good container and good soil, then plant correctly in the pot, water in the right way, fertilize with the correct nutrients, and finally control any insects and diseases which may attack you houseplants.
Choosing the Right Container
The container you choose must help your growing medium act like the soil in the plant’s natural habitat.
- It must be large enough for the roots to grow well and to anchor sufficiently to hold up the top. It must provide enough soil to hold sufficient water, nutrients, and air for the plant’s support.
- It must allow excess water to drain out of the bottom
- It should be made of a material which is tough and resistant to cracking and breaking. It is best if it can “breathe” by being made of a porous material such as fired clay.
Choosing the Right Potting Soil
After selecting the correct pot for your plant you must decide which type of soil you will use as a growing medium for your plant. In my years of observing houseplants and soils, I have concluded that the only good media in which to grow houseplants are the so-called “soil-less” or “peat-light” soils. Choose a medium with the following characteristics:
It should be light, and include a preponderance of peat moss, ground bark, vermiculite, and perlite.
It should hold enough water for good growth but not enough to become soggy, a condition which encourages anaerobic or toxic gases to form.
Developing Good Watering Practices
Knowing when and how to water is of prime importance when growing house plants. If we look at the way nature waters its plants, we see that, except in a very few places in the world, rain comes on no strict schedule. Heavy rain may be followed by periods of no rain. Plants survive very well under nature’s watering system. Here are some good rules to follow:
- Water when the plant and the soil in the pot need it, not on any arbitrary schedule
- Water each time the surface of the soil in the pot feels dry to the touch.
- Water thoroughly each time you water, being sure that the entire root ball in the pot is damp.
- Water more often when plants are actively growing and when the humidity is low
- Wilting of the plant is not necessarily an indication that the soil in the pot needs water. Too much water can cause root damage and water uptake, both of which also result in wilting.
Developing a Good Fertilizing Program
Plants must have certain nutrients to grow well. In nature, billions of years of soil development have provided the vital nutrients for the plants which inhabit a particular area. 
Plants taken away from their native habitat and placed inside our homes must also have nutrients. Since we provide a limited amount of soil in which the house plant must grow, we must constantly add these necessary nutrients to the soil in the pot.
Remember, when we aply nutrients for a plant’s use, whether indoors or outdoors, we are not feeding the plant. Plants produce food to feed themselves. We are applying fertilizers to give the plant the nutrients it needs to produce its own food. The criteria for plant nutrients are:
- Use a soluble house plant fertilizer and apply as recommended in the watering solution.
- Use both organic and inorganic materials in your fertilizing program.
- Fertilize when the plant needs it, not on a strict year-round schedule. Plants need more fertilizer when growing rapidly and less when resting.
- Be careful not to over-fertilize. Both organic and inorganic fertilizer nutrients are made up of chemical salts which will burn the plant if applied too heavily or too often.
Controlling Insects and Diseases
Insects and diseases occur on house plants just as they do on garden plants. Though the dry air in our buildings reduces the incidence of disease, there may be attacks of insects like aphids, scale, mealybug, spider mites, thrips (mainly on flowering plants), larvae (soft worms) on the foliage, and sow bugs and pillbugs on the roots. Several excellent house plant insecticides are available for these problems. Take a sample of the affected portion of the plant or the plant itself to your local plantsman or county extension agent for identification and recommendations of control measures.
Handling the Transition Period
Twice a year, house plants go through their greatest trauma as you change from heating to air conditioning and vice versa. These sudden changes in humidity can cause severe problems. In the spring, or when the air conditioning is turned on, mist your plants several times a day or run the cold-air vaporizer during the daylight hours. Gradually reduce the number of misting or number of hours in which the vaporizer runs until the roots have become active enough to replace the moisture being lost from the leaves.
In the fall, there is generally a lag time between when the air conditioner is turned off and the furnace is turned on. The trauma then is not as great, because the plants have time to adjust on their own. But you should watch them for signs of wilting of the succulent growth at the end of each branch. Apply the mist or run the vaporizer to help the plants adjust to their new situation.
Whats Next: Getting Started: Your Adventure With House Plants
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