Answer: Avocados are tropical plants but they grow surprisingly well in the average home environment.
I assume your avocado is in a pot with regular potting soil at this point. Keep your new tree in bright light (but not direct sunlight at first). Once it has adjusted to being in a pot (I wasn't sure when you potted it up), move it to the brightest location you have. When the stem is about 12 inches tall, pinch out the tip to encourage branching. The result will be a multistemed plant. If you don't pinch out the top, you'll get a tall, skinny, leafless stem with foliage appearing only on top.
Give the seedling plenty of light, the brighter the better. You will need to repot it into larger containers as it grows or it will quickly become very unhappy! Fertilize it with the low rate of a liquid plant food periodically. Keep the soil moist but not soggy and your plant should do well.
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