Answer: If you keep your philodendron in a four inch pot, you will need to do something to rejuvenate it periodically and the soil will need to be replenished or else it will begin to look poorly. The easiest way to maintain a small philodendron is to take cuttings from the plant once it gets too big for the pot and use them to start a new smaller plant. But if you want to try to keep one going, here are some suggestions: prune back the top as needed to keep the size you want. Each spring, rootprune the plant and repot it into fresh soil. Do not fertilize it for the first few months, then use a very low dilution of a water soluble fertilizer for foliage plants only during the summer months. Keep it in a reduced light area rather than a good bright light and be careful not to overwater it since it should not grow too much.
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