Answer: Excessive browning from the base and working up the plant is sometimes due to overwatering. This plant is very tolerant of dry soil so you should not need to water it too often. To know if you need to water, check the soil with your finger. If it is still damp do not water yet. Also, you may find that some of the oldest foliage drops as the plant continues to grow. This is sometimes more noticeable if the plant is not grown in full sun. Slow down on your watering and next spring after you take it back outdoors, you can pinch or prune the stem tips and the plant should develop new growth near the bottom and interior which will make it look dense and bushy.
Best wishes with your plant!
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