Answer: Corn plant leaf spotting occurs when the soil is too dry; when roots are compacted at the bottom of the pot; when soil pH becomes to acidic; and when mineral salts from excess fertilizer or hard water build up in the soil.
Pull the plant out of the pot. If you find only one or two large roots at the bottom of the rootball, then cut them off, add a little soil to the bottom of the original pot and put the plant back in.
If you have a mass of large roots wrapped around just the bottom of the rootball, then pull them loose and cut the big ones off. Add an inch or two of fresh soil to the bottom of the original pot and put the plant back in.
If you find a mass of roots completely surrounding the entire outside of the rootball, then loosen these roots and repot the plant into a pot one size larger. Never add soil to the top of the rootball.
If your local tap water is hard, then use filtered or distilled instead.
Hope this information helps!
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