Weeping clay pots
My plants are on a covered cement deck. I've always had great luck with clay pots. All of the sudden last week, a large pot started dripping a rusty, watery substance. It's all around the top, and even though I wipe it clean, the next morning it's dripping again. Now the other pots are damp and dripping this rusty liquid. Will this hurt the ferns? These are not new pots. All of the pots are on plant stands, not on the cement.
Josephine County Oregon
This website from the University of Arizona Extension offers a lot of information about caring for your terra cotta pots: http://calsmail.arizona.edu/pipermail/arid_gardener/2004-December/001707.html.
It sounds as though you are not letting the pots sit right on the cement, which is good for the longevity of the pots. Did you do something different, such as using a different fertilizer or changing your water source? But recognize that clay pots are very porous and subject to freezing, thawing, and cracking over time (the article mentions a five- to ten-year lifespan) and will eventually "melt away" just from watering. Maybe you are seeing liquified clay oozing from the pots. If it is clay, it won't hurt the plants, but you might want to think about eventually replacing the containers.