Gardening
The White Residue on Your Terracotta Pots May Be Harming Your Plants — Here’s How to Avoid It
Your garden will thank you.
We focus so much on our favorite houseplants, but the pots we put them in need attention, too. If you are a fan of terracotta pots, it’s important to make sure that white residue doesn’t build up on the surface. It’s a sign that the clay material is absorbing too much moisture from the plant, and can cause fungus and mold to grow.
At first, it seems like this is just a regular thing that shows up on terracotta over time. However, the experts at Hunker note how the unglazed clay finish allows the material to absorb chemicals from tap water and the plant’s fertilizer. This causes discoloration on the pot that usually starts out white and then turns a slightly darker color. The residue isn’t toxic or harmful as long as it’s only on the outside of the pot, but if it spreads enough to have direct contact with the soil it’s not a good thing.
Switching to glass and ceramic planters can help avoid the issue entirely. According to plant expert Kierslyn Kujawa, these materials aren’t porous, so excess chemicals or moisture from the soil won’t leach into the pot itself and your planters won’t start to turn different colors. Plus, their smooth and glazed surface is often much easier to clean. Plastic pots are also worth considering if you’re looking for a cheaper yet durable option that’s less prone to leakage. We have a handy list of outdoor planters that can pretty up your porch and avoid those pesky white stains!
If you don’t want to part ways with your beloved terracotta planters, Kujawa says that spraying a clay sealant like Plaid Clay Pot Sealer (Buy on Amazon, $12.05) on the inside of the pot before planting prevents moisture from escaping. For pots that already have residue, you can try The Houseplant Hobbyist’s tip of emptying the pot, soaking it in warm water for an hour, and using a stiff brush to scrub it off. It definitely requires some elbow grease and patience, but it’ll keep mold away and leave your terracotta pots looking like new.
Whether you try a new planter or take extra care of your current ones, your houseplants will thank you by continuing to thrive and grow!
