by Mark and Ben Cullen
A successful gardener is someone who has learned how to think like a plant.
Just like fishing: the person who always seems to catch their limit knows where the fish are and most importantly, knows what motivates them to take the bait. They think like a fish.
Your indoor plants are no different than your outdoor garden plants, except that we expect them to perform during winter: the shortest and driest days of the year.
With the sun at the lowest angle in the sky and the humidity in your home not likely higher than 20%, it is no wonder some plants protest by dropping leaves, flowers or appearing generally bedraggled.
Here is our primer for thinking like a plant during the toughest time of year to grow them:
Water. Resist the temptation to water indoor tropical plants until they need it. How do you know when that is? They will tell you. A spathiphyllum (peace lily) will droop its leaves when it is thirsty and ready for a drink. A poinsettia will also, as will most leafy foliage plants and flowering cyclamen.
Slightly droopy leaves are not a sign of neglect, they are a stomach growl: your plant is sending you a message that it is time for a good drink. Do not allow plants to stand in water that drains into the saucer below the pot for more than a couple of hours or you may risk over watering. Do not fertilize indoor plants at this time of year unless they are actively growing.
Some plants do not provide visible signs of thirst. Cactus, leathery leafed sansevieria (snake plant) and African violets require something else: the finger test. Push your finger into the soil about two or three centimetres deep. If the soil is not cool, then it is dry enough to water.
Light. Not only does the sun shine for only a brief time each day this time of year, the intensity is very low. The result is that many sun loving plants, like your tropical hibiscus and bougainvillea are in a state of mild shock. More accurately, they are semi-dormant. The result may be falling leaves, lack of flowering and no new growth. This is a time to let tropical plants dry more deeply than in summer when they are in full-on growth mode. It is helpful if you can add supplementary light, especially if you have high expectations for esthetic performance in a Canadian winter. Only grow lights really have an impact in this regard. Be sure to follow directions on the label that will suggest how close a light needs to be to your plants to have a positive impact.
It helps also to shift your expectations of your tropical plants this time of year. Nature did not design them to perform in a Canadian winter as well as they do during our growing season. Think of winter as a vacation period for plants, a time when they can rest and relax in preparation for an active growth cycle come late spring and summer.
Bugs. The dry air in our homes is an invitation to mealy bugs, aphids and the toughest of them all, red spider mites. Mealy bugs have the appearance of thin cotton batten, aphids are shaped like reverse light bulbs, the bulged end is their rear. Aphids are about the size of the head of a pin. Red spider mite is hard to spot but are mostly found on the underside of leaves. Hold a sheet of white paper under a plant and give it a light shake: if small red dots appear on the paper you have red spider mites.
The solutions to bug problems this time of year are many.
Mealy bugs can be wiped out using a cloth soaked in rubbing alcohol.
Aphids and spider mites will be discouraged by a daily blast with a stream of tepid water from an atomizer.
We encourage you to experiment with different plants in different windows of your home. Soon enough you will know what works best for you and before you know it, you will be thinking like a plant.
Mark Cullen is an expert gardener, author, broadcaster, tree advocate and Member of the Order of Canada. His son Ben is a fourth-generation urban gardener and graduate of University of Guelph and Dalhousie University in Halifax. Follow them at markcullen.com, @markcullengardening, and on Facebook.