Indoor plant problems are common so midwinter is a good time to check their health. Dust, bugs and fungi can sneak in and are best taken care of promptly.
Most of us are approaching the mid point of winter, if winter is defined as the time when tender plants are indoors rather than outside. For some the plants have been inside for just a few weeks and for others it has already been a month or two, but regardless of the time, the New Year it is time to assess the health of those plants, and avoid indoor plant problems from insects and fungi.
Indoor conditions are different to the great outdoors. Outside the plants encounter anything from slight breezes to sharp winds; full sun to torrential rain and humidity levels that vary day to day. This cannot be replicated indoors. Humans tend to prefer an even temperature with natural light. The only breeze comes from the heating system, and with all but the best of us, the watering is sporadic. Additionally, the day length in the northern continents is also much shorter. This is obviously stressful to the plants and some go dormant. Overall though, the plants are weaker and this makes indoor plants more susceptible to problems. The calm, warm air however, is an ideal environment for insects and fungi to grow.
The first things to look at are the leaves of the plant. Dust and debris can inhibit pores from functioning correctly as well as inhibit sunlight from reaching the leaf surface. With a gentle stream from the faucet, or a sprinkler head on a watering can, rinse the plant thoroughly in the sink. Do not forget the underside of the leaf, as this is where most insects reside and lay eggs.
If you do see evidence of insects determine what they are before treating. Scale can be easily removed by hand, but a baby bud soaked in oil will also remove them. Eggs can usually be removed by holding the plant under a stronger stream of water. Again, use a baby bud to dislodge them if needed. Note that some infestations may also occur from the soil surface. Thoroughly water the plant. Let the water soak the whole surface and continue watering until the water comes out from the base. If you choose, now is also the time to add a weak fertilizer to the pot. A liquid one is best for this time of year, as you can adjust the dilution easily. Let all the water drain before replacing the plant on a saucer or back in its display pot.
By regularly checking for indoor plant problems in midwinter, and promptly dealing with any problems, plus giving the plant a good shower will ensure that you plants will remain healthy until spring.