This is about the time our ITs may be showing their ennui by exhibiting "symptoms". Certainly, they're as tired of short days with constant cloud cover and and low indoor humidity as we are. And that presumes we're watering correctly in response to these imperfect conditions. So, assuming they have good personal hygiene and are otherwise free of livestock and pestilence, here's an abbreviated troubleshooting guide. The caveat- "Probably" should probably be inserted in front of each bullet point. Why? Because it's as likely a combination of factors as a single one causing IT malaise in your collection.
Potato chip-crispy spots or lesions on leaves: Underwatering
Lesions that are soft, dark brown or water-soaked: Overwatering
Leaves are curling (either upward or under):
- Chilling (too close to a drafty window or door to the outside, room colder than the plant likes) and/or
- Plant subjected to temperature extremes (too high, too low) for some period of time
- Someone in charge of watering that let the plant go bone dry for weeks or months, and it's not a forgiving cactus or succulent?
- Is it a new adoptee that was just brought home from the greenhouse? In other words, has it been used to higher light and you've featured it in a window-less, light-less room resembling the inside of a sarcophagus?
- Did it get chilled on the way home by being outdoors unwrapped? Did it sit in a car while you shopped-'til-you-dropped for hours and the car temps got dangerously low?
Lower leaves turn yellow and drop:
- If it's just one leaf and it's the very oldest (lowest on the stem) that may be okay. Leaves don't live forever. Plants naturally shed old leaves that are shaded by the upper portion of the plant.
- Multiple leaves yellow? Has it been overwatered? Too much water, too frequently?
Leaf ends or edges brown, brittle:
- Humidity just too low for the plant (by far the most common reason)
- Erratic watering- plant is alternatively wet and/or dry
- Like Goldilocks, room "too hot", "too cold", never just right
- Fertilizing frequently while plant is on winter growth hiatus, and therefore not utilizing nutrients. We call that "burn"
- Just not enough light for the species you're trying to grow
- Room excessively hot and dry
- Plant regularly underwatered
- Overwatered on a regular basis and/or
- Left standing in a water-filled saucer or pot with no drainage hole frequently and for long periods of time
- Fertilizing frequently all winter long? S-T-O-P now. Those fertilizers salts are accumulating because the plant is not growing and therefore not using them OR
- Using hard water with high salt levels
- It's winter, full of short, cloudy days. Unless you have a greenhouse or full-length south or west-facing windows to maximize light to perhaps coax some growth from your plants, relax. This is normal for our winters. New growth should start peeking out as we approach spring.