TERRACOTTA POT LIP PROTECTION
Terracotta pots are great for houseplants because they breathe. They also absorb minerals, especially salt, from water and can get a crusty buildup on the rim. Leaves and stems that touch this buildup will sometimes wilt and die. To avoid this problem, you can wax the pot.
Save old candles and simply rub them around the rim of the pot to seal the terracotta. Any kind will do--colored, scented or plain.
Set the pot and the candle stub in the warm sun for an hour or so before rubbing. That way the wax rubs on easier and better penetrates the clay.
Every six months you may have to flush excess minerals from the potting soil by pouring water through the pots until it runs out clear. Waxing the rim of each pot saves scraping away the crusty deposits, and your plants almost never lose a leaf or a flower to mineral damage.
Shirley Watson, Smith County Master Gardener
Texas AgriLife Extension Service
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