My Indoor Houseplants

Houseplants do remove toxins from the air in your home. But how effective they are at improving indoor air quality depends on some other factors as well.

Firstly, houseplants can only remove VOCs ( volatile organic compounds) at a certain rate. The rate at which VOCs are removed from a room can be increased to a certain extent by adding more plants. We run into a problem in that houseplants take up space, the space in which we live.

There is another way we can ensure we benefit from our houseplant’s air cleaning work. We have to reduce the rate at which toxins are added to our room air. Some things we can do to help are:

- using paints and other decorating products that are designed to be more eco friendly when we redecorate.

- using eco friendly cleaning products when we clean that give off less VOCs.

- insisting on organic cleaners for carpet and upholstery cleaning.

- not smoking in the room. It does little good to have houseplants cleaning the air if someone sits in the living room smoking a big cigar or even a cigarette.

- dust the room to reduce the amount of dust particles. Dust particles are picked up by small movements of air and are carried around the room. We can see this in the dust collecting on surfaces and on the leaves of our houseplants.

Secondly, we can keep our houseplants acting as efficiently as possible by:

- keeping the leaves clean so that they can breathe and maximize the transfers involved in photosynthesis.

- provide the conditions the plant needs to remain healthy and strong. A strong healthy houseplant will be a better air cleaner than a sick weak plant.

By taking care of the houseplants and taking care that the materials we are introducing into our living space, we can get the best benefit from our indoor houseplants.

Much has been written lately about the ways indoor houseplants benefit us by removing volatile organic compounds ( VOC’s) from the air, but there are many other benefits our houseplants can and do provide.

-   Houseplants produce and give off oxygen, replacing the oxygen we remove when we breathe.

-   As the plants grow, they take up the water from the soil to use it in producing new plant material.  Some of this moisture is given off, raising the humidity in the room.  In the dry air of the winter, this makes the air easier for us to breathe, a definite benefit to those with asthma or other breathing problems.

-   Houseplants can make the visual impact of a room more pleasing.  They can round off sharp edges and provide a texture in a room filled with the straight lines and flat surfaces found in most rooms today.  They can add colorful accents to the decor and draw out the features of the other furnishings of the room.

-   They can create an ambience in a room that will create a calming effect.  This calming effect will reduce the stress levels felt by the occupants of a room.

-   Many houseplants have also been grown for their medicinal properties.  Many keep an aloe vera plant in their home for the ready fresh supply of the gel contained in the leaves.  This gel has long been used for the treatment of cuts and burns.

-  Many herbs can be grown indoor to provide a fresh source of garnishes and spices to season our foods.  They are also a good source of many nutrients our body needs.  Parsley, for example, may be used as a garnish on the plate or combined in the food ( as in pesto).  Parsley is an excellent source of vitamins A, C, and K.

These are just a few of the ways in which we benefit from growing houseplants in our home or office.

Each year when we buy our new poinsettia in December we think about how we can make it re-bloom for the next year.

To have a poinsettia plant that is full and attractive, you needed to cut the poinsettia back to about 3 to 4 inches in mid to late April. This will get rid of all the old growth and give a base for new growth to start.  It will also keep the poinsettia from getting too large.

Then after the new growth has established, you pinch back the poinsettia plant in early July. This will cause each of the new stems to branch out creating a fuller bush.

Now starting in late September, you need to give the poinsettia plant 12 to 14 hours of continuous darkness each day for 8 to 10 weeks to get the poinsettia to produce the colorful brachts in time for a December display.

You can do this by many methods, but it is important that the process is not broken. It must be done each day for the period. The darkness must be total. Room lighting for regular living will be enough to affect the process. Even the light from a street light outside can affect the production of the colorful brachts.

Some people will place the poinsettia in a darkened room at night. The curtains should be drawn and the room should not be visited during the 12 to 14 hour period. Even the turning on of the room light for a short period will affect the poinsettia.

Instead of using a room, you may use a closet for the dark period. Again the closet should be kept completely dark and the light should be blocked from getting in through the cracks around the door.

Another way is to enclose the poinsettia in a dark garbage bag for the 12 to 14 hours of darkness. The bag must be very dark and thick so as not to let in the light through the bag. Manufacturers of garbage bags are getting very good at making strong bags with thin sides and coloring them green. This allows too much light to pass through, so choose a heavy black bag. When using this method you also want to support the bag so that it does not touch the poinsettia leaves. Also during the daylight hours, lower the bag completely so that the poinsettia can breathe.

During this 8 to 10 weeks, the poinsettia needs to be returned to the bright light during the daytime. The poinsettia plant is still growing, producing the brachts or colorful leaves that we want.

Re-blooming last years poinsettia requires some patience, but you can produce a beautiful houseplant to add to your winter decorations.

Are your houseplants getting brown tips or edges? There are three main causes.

1. Low Humidity- If the humidity in your room is low and the houseplant requires a higher humidity, the tips and edges of the leaves may dry and turn brown. To keep this from happening, we need to raise the humidity around the plant.

We can group plants together in an area. All plants give off moisture, some more than others. If we group plants together, we create a micro environment in that area which has a higher humidity than the rest of the room.

A second way to raise the humidity is to place the houseplants on pebble trays. A tray with pebbles or gravel is placed under a plant. Water is added to the tray until it is just below the top of the pebbles. The water will evaporate around the houseplant raising the humidity.  Be sure the plant pot is clearly above the water.  If the plant pot is allowed to sit in the water, we can encounter another problem called root rot.

Misting is another way to raise the humidity temporarily, but for long term effects several mistings a day would be required.

2. Floride or boron found in normal tap water may build up in the leaves causing the tips to turn brown. Many houseplants, including peace lilies, are susceptible to this.  Allowing tap water to stand in an open container for a day will allow some of these gasses to evaporate, but this may not be enough.  It is best to use rain water or distilled water to water your houseplants.

3. A build up of soluble salts from fertilizer will also cause leaf tips to turn brown. If you see a white substance on the top of the soil in your plant pot, a build up of fertilizer salts is the likely culprit. To clean out the excess salts, take the plant to a sink ot bathtub (or outside) and pour enough water with no fertilizer into the plant pot so that at least half of it runs through the plant and out the bottom of the pot.   Wait about 5 minutes and pour that same amount through again.  This time it will all run through.  Repeat once more.  This will wash the excess salts out of the soil.  Don’t fertilize the plant again for 2 to 4 weeks.  When you resume fertilizing, reduce the strenght of the fertilizer solution being used.  At nurseries, they always pour enough water throught the plant at each watering to leach out the excess salts.  This is not always practical in our home setting.

We need to water houseplants less in winter

As the heat of the summer passes we find we need to water houseplants less. There are several reasons for this.

The houseplant needs more water when it is actively growing.  In the fall the growth rate slows and the houseplant will need less water to increase the size of the plant.  Water will still be needed to maintain the houseplant at its current size and health.

One of the reasons the growth rate slows is the shorter daylight hours. The houseplant needs the light for the process of photosynthesis, the process of plant growth, to take place. Also the intensity of the light decreases because the sun doesn’t rise as high in the mid-day sky. Because the light intensity decreases, the plant will not grow as quickly and will require less water.

When the temperature is hotter in the summer, the rate of evaporation increases. We need to water houseplants to replace the water that is lost by evaporation.

Although houseplants will need less water during the winter months, proper houseplant watering during the winter months is still essential to ensure the health and beauty of your houseplant.  At this time of year we need to be aware of how much water we are giving our houseplants.  This is the time of year we are most likely to over water our houseplants.

During the summer we may see the leaves of some of our house plants appear to be wilting. We immediately think of watering them, but this may be the wrong thing to do. It may actually harm the plant.

In the heat of the summer more water will evaporate from the leaves. In a room that is not air conditioned, the temperature may rise to over 80 degrees F. At that temperature the house plant may be unable to move enough water up from the roots to the leaves to replace the water being evaporated. Peace lilies are one of the first house plants to show this condition.

To determine if the house plant needs watering, we need to see if the soil in the pot is dry. Test it with your finger. If so, water the plant. If not the houseplant does not need watering and we need to take other measures.

The cause of the wilting is too much water evaporating from the leaves. The rate of evaporation can be reduced in two ways.

Firstly, we can reduce the rate of evaporation by increasing the humidity around the plant. The humidity can be raised by using pebble trays around the plant. Place pebbles in a tray and fill the tray with water nearly to the top of the pebbles. Place the plant in its pot on top of the pebbles. Do not let the bottom of the plant pot stand in the water.

The best way however is to reduce the temperature of the room to a temperature the houseplant is more suited to. This is normal room temperature at other times of the year. The plant is developing to live in this temperature as it grows, building a root, stem, leaf balance suited to this temperature.

If the temperatures outside the house are lower than in the room, the temperature may be lowered by opening windows and providing more ventilation.

Drapes or awnings can be used to stop the sunlight from shining directly into the room. Glass windows not only let in the light, they also allow the heat of the sun’s rays inside. Covering windows on the sunny side of the house will help keep interior temperatures lower.

Before you water that wilting houseplant, find out if that is really what it needs.

Indoor plant watering is a subject that many do not understand well. We find that some of our indoor plants need more water than others. We also see that plants seem to need different amounts of water at different times of the year. Lets examine some of the factors that lead to these differences.

Different types of plants need different amounts of water. Those with stiff, shiny leaves need less than those with softer leaves. less water evaporates from the stiff, shiny leaves like those of a pothos than evaporates from the softer leaves of a fern. Succulents, like cacti or aloe vera, require very little water.

Larger indoor plants need more water than smaller versions of the same plant. Larger plants will have more growth and more leaf surface area.

Indoor plant watering is also affected by the consistency of the soil. The sandier the soil, the faster it will dry out. The sandy soil does not hold the water as well as a less sandy soil.

Indoor plants also need more water during the part of the year they are growing most quickly. As well as carrying the nutrients to the leaves, water is used in the growth process.

The amount of light a plant receives also affects indoor plant watering. This increase in light can be due to the longer days in the summer. The longer days stimulate many plants to put on a spurt of growth requiring more water. The increased strength of the sun in summer will also increase plant growth. The strength of light is also affected by the location of the plant in the home. How near is it to a window and what direction does the window face.

The humidity of the room affects the amount of water a houseplant needs.  A houseplant in a humid room will require less water than the same plant in a room where the air is drier. Indoor heating will cause the air in the room to become drier.

The room temperature will affect the indoor plant watering requirements. As the temperature of a room rises, a houseplant will require more water.

These are just some of the factors that affect indoor plant watering needs. We need to adapt our watering schedules to accommodate the watering requirements of different indoor plants at different times of the year. We need to water houseplants according to their needs, not some predefined schedule.

We can often grow a new indoor houseplant from seeds we acquire in our daily lives.

One day, while eating a Christmas orange, I noticed that the pips had already started to sprout. (It was late in the season).

I gathered together several and planted them in a pot of regular potting soil.After a couple of weeks the new plants broke the surface and started growing leaves.

I kept the pot in a bright window with no direct sunlight and watered when the soil became dry.  What is shown in the picture

is just under two years growth.  Four plants were allowed to continue growing in the pot.  I believe that the growth has been suppressed because I have not yet applied fertilizer and because the plant has become pot bound.

Next spring I will repot the orange tree into a larger pot and fertilize it.  I expect it to grow rather rapidly to a new size threshold.  By keeping the plant in a smaller pot than it would like, many plants can be kept to a smaller size.  In bonsai, plants are kept to a smaller size by using a smaller, shallow pot and by selectively pruning the tops and the roots.

I have grown several new indoor houseplants from seeds that have arrived in the grocery bag. With these new citrus plants I knew what they would look like, but with other plants there is also anticipation and surprise when you see your new indoor houseplant develop.

Does anyone else have a story they would like to share?  If you click on the blog title, you can leave your comment or your experience.

At this time of year many are thinking of bringing plants back into their homes that they had moved outside for the summer.

I personally don’t move houseplants outside for the summer for several reasons.

1.  Houseplants, when moved outdoors, will need to adapt to new growing conditions for the summer.  Then, when they are returned to the indoors in the fall, they will need to re adapt to the indoor growing conditions.  While many houseplants will adapt easily, others will not.  these plants will have to be moved to a location with less light before their final move indoors.  This will enable them to adjust gradually to the light level they will be in during the winter.

2.  Houseplants that have spent the summer outdoors may have collected some insect pests to bring inside with them.  They will need to be thoroughly examined , cleaned and isolated from the other indoor houseplants until we are certain that all insect pests are gone.

3.  When the houseplants are brought back indoors, we need to find a place to put them- a place that is suitable for the houseplant.  This location will need to have sufficient light, proper temperature, free of hot and cold drafts, and sufficient room for the plant to grow ( and they will have grown during the summer).  During the summer we may have acquired new plants, redecorated our home or made other changes that make the old location unavailable.

4.  Lastly is the question of timing.  We need to wait long enough in the spring so that night time temperatures do not drop below what the houseplant will tolerate.  In the fall we must return them indoors before the first “killing” temperatures occur. For many indoor houseplants it does not even need to go down to freezing to be deadly to the plant.  Also we have all heard the term “unseasonable temperatures”.  A sudden cold snap in the spring or late summer can shorten the safe window by months.  Unusual cold spells can leave you scrambling to protect your houseplants outdoors.

I have chosen to enjoy the beauty and feeling of my houseplants indoors all year long.  For my yard, I choose a selection of other plants suited to growing outdoors.

I was given a cyclamen persicum about 19 months ago as a gift.  The flowers had faded but the leaves were still lush and green.  I continued to give it water.

About 2 months later, more flowers began to appear, beautiful, large red flowers.  Since then it has flowered continuously for 17 months.

This past spring most of the leaves yellowed and died- but the cyclamen kept producing more and more blooms.

In the spring the florist’s cyclamen usually stops producing flowers and the leaves yellow and die as it goes into a dormant state.  The food stored in the tuber is used to restart the growth in September.  I really have no explanation why my cyclamen persicum refuses to go to sleep.

For most of this time it has been located about 2 feet from a northwest facing window, getting bright indirect light.

I have paid no special attention to temperature, and during the heat of the summer the temperature often rose to over 90 oF.

I am fortunate here in that the humidity is usually about 50% and I saw no indication that this was a problem.

The treatment this florist’s cyclamen received would best be described as benign neglect, being given only the basic necessities of light and water.

Was this plant responding to the appreciation it received from me and others who admired the continuing display?  Fortunately it wasn’t able to read any of the articles and websites written on how to care for a cyclamen persicum!