Q: I’ve had these plants for many years. All of a sudden over the last six months or so, some of the leaves have yellowed and browned and died. I water weekly and do very little else, and they have always thrived. Have I started doing something wrong?
A: Overwatering often is to blame when leaves of pothos, also known as Devil’s Ivy, turn yellow and brown. The plants thrive best when the soil they are growing in is allowed to dry between waterings, and too much water will result in a fungal disease often referred to as “root rot.”
Keeping any plant on a set watering schedule, say, once a week, isn’t ideal because conditions change throughout the year: During winter, indoor heating dries the air and may mean plants need more water. However, most houseplants do slow down during this time, as sunlight is reduced.
Timing is delicate, because allowing soil to become too dry will result in a wilted, stressed plant and potentially some tissue damage. It’s best to plunge your finger into the soil and feel for yourself whether the root area is dry.
Remove affected leaves, water only when the soil is slightly dry and resume fertilizing with a 10-10-10 or 20-20-20 product now that spring has arrived.
Q: I have two Peace Lily plants, one slightly smaller than the other. The leaf tips of the larger plant show many brown, frayed edges, while the other smaller plant has just a few frayed edges. They both get indirect sunlight, and I water them generally every two weeks. I’ve had both plants for about seven or so years. What am I doing wrong?
A: One reason Spathiphyllum leaf tips turn brown is overexposure to sunlight, which doesn’t seem to be the case, as you’ve noted your Peace lilies are growing in indirect light. This also can occur when plants are over- or under- watered, but if you’ve had them on the same watering schedule for seven years and you haven’t moved or altered their growing conditions, my best guess is they are succumbing to a buildup of minerals.
Minerals, such as calcium, are present in tap water, and over time can accumulate around plant roots, causing distress and inhibiting them from properly performing their functions.
Check the pots’ drainage holes. If you see a white residue, then you can be sure mineral deposits are contributing to your plants’ decline. However, an absence of this visual clue does not necessarily mean buildup around roots is not to blame.
Using sharp scissors, trim away browned edges, cutting about one-eighth of an inch into the healthy part of leaves. Next, place pots in the sink and flush the soil with plenty of bottled water until it drains freely from the bottom. Going forward, watering exclusively with bottled water should resolve the problem.
DIEFFENBACHIA
Dear Jessica: I read your column about the woman who was looking for a home for her inherited and overgrown Dieffenbachia. I also inherited three very old Dieffenbachias when my mother died 10 years ago. I had learned from her that you could cut pieces and easily root them in water or even directly in soil. I have propagated many babies from the originals. Some live in water for years. Others I have potted and shared with family and friends. I hope she rescues that plant! It will be a source of many offspring.
— Deborah Davenport, NY
Dear Jessica: I just had to write to you about the orphan Dieffenbachia in your recent column. I’ve had my own Dieffenbachia, which I rescued from the windowsill of an office at Huntington Hospital in 1974. It was about 12 inches tall and was growing in a jar of murky green water. The housekeeper assigned to our office told me how to take care of it, and her advice was perfect because you can see a great-great-grandchild of the original plant rooting on my dining room windowsill.
At one point, the original plant grew to be about 7 feet tall, and I draped it over the top of a bookcase, where it continued to grow another 3 feet toward a bay window, and another 2 feet across the drapery rod. It fell over and cracked one day, so I cut the longest, leafless stalks off, and put 12- to 18-inch sections into jars of water. Well, it’s 44 years later and there are pieces from that original plant still growing on my windowsills.
I’ve found that the best way to prevent that kind of unruly growth is to cut back the new growth. Periodically, I’ve had to cut it way back to about 3 to 4 inches. When there are straight sections with leaves, I just plop them into water, and they eventually root and start sprouting new leaves. These water-rooted sections easily tolerate being potted, where they continue to grow.
— Nancy Cuccaro, Southold, NY
Dear Deborah and Nancy: The beautiful thing about many plants is that, as you’ve discovered, they can be propagated with little effort. Not only does this produce free plants, but it fulfills an emotional need when a plant holds sentimental value. Thanks for sharing!