The dip in temperature near windows, drier air, and indoor heating can change your home’s environment and
adversely affect your plants.
There are six key elements one should always consider when caring for indoor plants: light, temperature, water,
air circulation, fertilizing, and plant cleaning. Over-doing or under-doing and/or giving too much or not enough
of any of these could very well hurt your plants.
Light
In general, darker leafed plants require lower light, and most plants do well in medium light. Blooming and
variegated plants tend to like high light and can lose their colour if they don’t receive enough light.
When deciding where in your house to place your plants, consider where your windows are located.
High light plants do best in rooms with southern exposure, medium light plants do well with east or west exposure,
and low light plants do well with northern exposure. If you place plants in a window, try to keep a 12” barrier
between your plants and the window-pane to avoid sun scorch and allow for air circulation around the plant.
If you don’t have the proper natural light in your home for a particular plant’s needs, artificial light can
be a fine substitute. Fluorescent lighting is fine for plants as are “High Intensity Discharge” lights though these
are more expensive.
Not sure if your plants are liking the light they’re receiving? Spindly stretched out growth, small leaves
that are cupped or curled, and stunted growth and yellowing leaves are signs a plant isn’t receiving enough light.
Plants that are wilted, look washed out, or have transparent spots on their leaves are getting too much light.
If you see any of these problems, move your plants accordingly.
Temperature
Generally, normal indoor home temperatures do not cause problems for plants, and there is a good degree of
flexibility in what houseplants can endure. Avoid placing plants near heating vents or in front of fans however,
and don’t place medium or low light plants in south facing windows as the heat (and light) will harm them.
It can be difficult to tell if a plant has endured too much cold or too much heat, but wilted leaves that yellow
and fall off are associated with too much heat and light. Wilted or curled leaves that are discoloured or brown
and dropping are signs a plant has faced temperatures that are too cold for it.
If you see this happening, prune the affected parts and move your plant to a different location to see how it does.
Tip:
If you are buying a plant as a gift for someone this holiday season, make sure it’s well protected
on the way from the store to the car. If it’s below 40-45 degrees Farenheight outside, cover them or they could get cold shock.
If temperatures are below 20 degrees Farenheight, double bag plants before going outside! Also, don’t let plants sit in the
car for long periods as they can easily get too hot or too cold.
Water
Soil affects the watering of your plants since it is what holds moisture and determines how water drains from
the pot. Soil should hold moisture but drain well. If you are repotting, good soil is important, so avoid the
cheap stuff and spend a little extra for quality soil.
One of the most common causes of dead houseplants is over watering. Water that is allowed to pool and sit in
the bottom of a pot can cause root rot. The plant dies from the bottom up. To avoid this, pour out drainage
saucers or trays after 30 minutes. The plant, by this time, will have absorbed all it can. Signs that you are over
watering include gnats (fungus flies) hovering around your plant. The gnats plant their eggs in the top inch or so
of soil that is consistently moist. If you have gnats, spray the soil with diluted dishwashing liquid and then
let the soil dry out to kill the eggs.
Signs of under watering your plants can include leaves that start to drop off, leaves that become crispy
or wilted and/or take on a curled or cupped appearance or, with spider plants, leaves that may start to look
Quality of water can matter too. Water that has gone through a softener can be too salty for plants.
Substitute distilled water. White build-up around the edges of the plant’s pot is a sign that the water being
used is too alkaline. Distilled water is best to use in this situation as well. And, while a nice idea, rainwater
can be too polluted.
Finally, always use tepid water as water that is too hot or cold can damage plants.
Air circulation
This is something that is not usually considered in plant care but plants need decent air circulation in order
to be their best. Too much heat from a vent or heat register, or too close a location to an air conditioner can
dry out the plant’s soil too quickly. Direct any forced air away from plants.
If plants don’t get enough air circulation, soil can fail to dry out and fungus or powdery mildew can result.
Interlinked with air circulation is temperature, which I discussed last article. Remember that air that is too
hot or too cold can harm plants. In this winter weather, if you’re buying plants, cover them if the outside air
temperature is less than forty to forty-five degrees Farenheight.
Fertilizer
When choosing a fertilizer, generally an “all around” one will do. You want to look at three numbers that
plant fertilizers will have listed on the box or bottle that represent the amounts of nitrogen, phosphate, and
potassium they contain. A 10/10/10, for example, means all the properties are in equal amounts in the fertilizer.
A solution like this is best for green houseplants. Look for a 5-10-5 for blooming plants, and keep in mind that
some plants need a special fertilizer. Evergreen bonsais, for example, are acid loving and need a special type
of fertilizer. If you aren’t sure, do a little plant research first.
Choose a water-soluble solution, as it is less likely to burn the roots of your plants. If you choose fertilizer
spikes, insert them to the outside edge of the pot, away from roots, to avoid burning them. And don’t over-fertilize
as this can also burn your plants and kill their root systems. Fertilizing once every two weeks, or, at minimum,
once a month usually suffices.
Other fertilizers such as earthworm castings, which are organic, are good for use on plants you are planning
on consuming later. (Always use organic fertilizers on plants you will be using in cooking). Fish emulsion is
also considered organic and is great for green houses, but beware, it has a really strong odour.
Plant cleaning
Just like a lot of other living things in the world, plants need “baths” too. Pores in plant leaves
can get clogged with dust, which makes for a less happy and less healthy plant. Giving them a “bath” prevents
disease and is as easy as misting them periodically and then gently wiping off the leaves, or taking warm soapy
water and gently wipe off the dust that collects on them. You can also take them into the shower and give them a
tepid bath.
There are some exceptions. Fuzzy leafed plants should be brushed off if they get dirt or dust on them, vs.
washed, and succulents don’t like to be cleaned.
Otherwise, bathing your plants will help keep them healthy and happy.
Plant Care
In general, darker leafed plants require lower light, and most plants do well in medium light. Blooming and
variegated plants tend to like high light and can lose their colour if they don’t receive enough light.
Generally, normal indoor home temperatures do not cause problems for plants, and there is a good degree of
flexibility in what houseplants can endure. Avoid placing plants near heating vents or in front of fans however,
and don’t place medium or low light plants in south facing windows as the heat (and light) will harm them.
It can be difficult to tell if a plant has endured too much cold or too much heat, but wilted leaves that yellow
and fall off are associated with too much heat and light. Wilted or curled leaves that are discoloured or brown
and dropping are signs a plant has faced temperatures that are too cold for it.
If you see this happening, prune the affected parts and move your plant to a different location to see how it does.
Soil affects the watering of your plants since it is what holds moisture and determines how water drains from
the pot. Soil should hold moisture but drain well. If you are repotting, good soil is important, so avoid the
cheap stuff and spend a little extra for quality soil.
This is something that is not usually considered in plant care but plants need decent air circulation in order
to be their best. Too much heat from a vent or heat register, or too close a location to an air conditioner can
dry out the plant’s soil too quickly. Direct any forced air away from plants.
When choosing a fertilizer, generally an “all around” one will do. You want to look at three numbers that
plant fertilizers will have listed on the box or bottle that represent the amounts of nitrogen, phosphate, and
potassium they contain. A 10/10/10, for example, means all the properties are in equal amounts in the fertilizer.
A solution like this is best for green houseplants. Look for a 5-10-5 for blooming plants, and keep in mind that
some plants need a special fertilizer. Evergreen bonsais, for example, are acid loving and need a special type
of fertilizer. If you aren’t sure, do a little plant research first.
Just like a lot of other living things in the world, plants need “baths” too. Pores in plant leaves
can get clogged with dust, which makes for a less happy and less healthy plant. Giving them a “bath” prevents
disease and is as easy as misting them periodically and then gently wiping off the leaves, or taking warm soapy
water and gently wipe off the dust that collects on them. You can also take them into the shower and give them a
tepid bath.