Mineral deposits can harm plant roots

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 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?

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 underwatered, 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 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.