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Can I put coffee grounds on my houseplants? What about cooking water?

Since I know I can compost coffee grounds, would it be OK to put the grounds on houseplants? Also, I like to conserve water. Can I use water from cooking sweet corn or other vegetables on my houseplants?
Submitted by BHGPhotoContest

Coffee grounds are fine additions to compost, and you can toss the entire batch-including the filter-onto the compost pile without any concerns. But indoors, be careful using coffee grounds. As the grounds decompose, they'll harbor fungi, which can attack and even kill your plants. A thick layer of grounds may also keep soil excessively moist, which can harm your plants' roots. If you use grounds indoors, do so only sparingly, and avoid watering the plants unless the soil is dry to the touch. Coffee grounds acidify soil slightly, so although that may benefit gardenias and azaleas, which prefer acidic soils, it won't help an African violet. Cooled vegetable cooking water is fine to add to houseplants. Do so in moderation. Reuse only unsalted cooking water; salty water could burn your plants.

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I used coffee grounds in my houseplants and to my horror, I also, grew a "healthy" infestation of meal moths. I was really puzzled when meal moths began to flutter all around my house since I keep no meal, flour, etc. in my cabinets. It took me awhile to find their incubation places. So no more coffee grounds in my indoor plants! And best of all the meal moths are down to an occasional one or two!
Submitted by letitia.vaughan