Q.Outdoor potted avocado tree
The tree is three years old and three foot high. The leaves have gone brown over the winter. What can I do to revive the plant?
Was the potted tree brought inside for the winter or left outside? If it was left outside, it may have suffered a cold injury because avocado trees do poorly where freezing temperatures may occur. You can read more about cold injury and learn about the prescribed treatment at the following link:
If the tree was brought inside over winter, where was it located? Avocado trees need to be in a location where they receive bright light. Also - is it possible that maybe your tree was over or under-watered (feel the soil - is it damp/soggy or dry to the touch?)?
For more information about growing avocado trees in containers, please visit the following link:
https://www.gardeningknowhow.com/edible/fruits/avocado/indoor-avocado-plant-care.htm