Healthy houseplants can refresh a room. But they are so often unhealthy because not given the growing conditions they need to thrive. Underwatered, overwatered, root bound, given too much or too little light, and almost never afforded the degree of humidity they prefer. Weakened by neglect and/or overzealous care, they succumb to spider mites or aphids or they simply drop leaf after defeated leaf until, denuded, they succumb completely.
I speak from experience regarding the woe-beset houseplant. That said, there has been a gradual but unmistakable improvement in my relationship with my green housemates.
What is Working:
1. Source your house plants carefully. I try to buy from local shops and nurseries that specialize in houseplants rather than big box stores, after a number of negative experiences with overwatered plants and various plagues. Think twice before buying plants online unless absolutely unavoidable, as you don’t have the chance to assess the health of the plant before buying and the journey to your doorstep puts the plant under a good deal of stress, which can lead to problems later.
2. Locate plants thoughtfully. Group those with similar requirements together, and take account of the microclimates in your house. Factors to consider are strength/directness of light and humidity. The room in which our gas fireplace is located is home to desert plants that benefit from the dry heat, while ferns and tropical plants are largely situated elsewhere. Plants that need particularly high humidity are located in the kitchen or bathroom.
3. Using a water meter to gauge soil moisture before watering. The look and feel of the top layer of soil can be misleading. The water meter takes a deeper reading. This is a minor investment that will go a fair way to prevent over and underwatering, which is usually at the root of houseplant problems.
4. Checking moisture levels and watering ferns and tropical plants more often if needed. General guidance regarding frequency of watering during different times of year must be adjusted for different kinds of plants. If you simply water all plants once a week, for example, you are likely to end up with dessicated ferns and rotting cactus.
5. Potting with appropriate soil. The soil medium you choose for each plant determines nutrient level and, all importantly, drainage. A standard potting soil retains much more moisture than does a cactus mix. Epiphytic plants are usually best served by an orchid mix.
6. Using organic fertilizer on a regular basis. I used to balk at fertilizing my houseplants, mostly through sheer laziness. I have embraced the necessity of fertlizing and now add a small amount of powdered organic fertilizer to each can of water about once a month for plants othwr than cactus. As a consequence, my plants seem healthier and I have observed significantly more growth than previously.
7. Increasing humidity for ferns and tropical plants via atomizer and/or humidifier(s). This is another lesson I have been slow to learn. This year, I have finally purchased my first functioning atomizer. The previous ones I bought were cheaply made and stopped working almost immediately. I suspect that I need to mist the ferns and tropical plants more frequently, but I’m doing my best. After a good deal od research, I purchased a cool mist humidifer that can be set to maintain a certain percentage humidity and has a water tank large enough to run all day. This is such a new addition that I can’t comment on its benefits for my houseplants, but the air seems more comfortable to breathe, which is a definite positive.
8. Observing plants carefully for signs of stress or infestation. Leaves yellowing, turning black, browning at the edges or shriveling are communicating the plant’s needs. Determing what, precisely, these messages mean is the next challenge, and while the internet can be a helpful resource, be aware of the source of your information. In the case of infestation, careful observation of the signs (frass, webs, honeydew, actual insects or egg sacs, etc.) and symptoms (holes or discoloration in leaves, stunted growth, etc.) are critical to making an accurate diagnosis. What to do when you have identified a problem? Evaluate whether cultural adjustments are needed. For example, if leaves are turning black, do you need to reevaluate your watering schedule? If there is an infestation of spider mites, should you increase humidity? Outdoors, in the garden, I avoid using any form of pest control and let predators and parasitoids do their work. Indoors, I do not have that luxury. Natural chexks and balances not being in play, I isolate infested plants and use organic pest control methods like horticultural oil, neem, or soap to address infestations before they spread.