Question
I have an avocado tree that has been in the ground all summer.  Should I put it in a pot and put in my greenhouse.  I live in Central Texas.  Thanks so much

Answer
Hi Betty,
Thanx for your question.  I don't believe the avocado is hardy enough to survive a Central Texas winter.  Avocados are typically grown in the Rio Grande Valley and other agricultural areas of South Texas.  Even though I don't live in Texas, I frequently consult with documenation from TAMU as it is very reliable for a number of horitcultural and agricultural subjects.

If you can, I would dig the tree up and put it in a large tub.  You might want to consider buying a pot on rollers to make it easy to move the tree in and out of the cold.  The tree will go into a period of dormancy and may appear to be dying or not doing well when you take it indoors.  Always face trees like this in an area of the home that gets the most sunlight.  Preferable an eastern or southern exposure.  I was able to keep lots of tropicals alive because I had a patio door that faced the east.  My plants seemed to do okay with this until beneficial weather returned in the spring.  Water just enough during the winter to keep the plant from drying out and do not feed.  I kept an avocado in a pot alive for 5 years.  I know someone who kept a 7 foot lemon tree alive in their kitchen for more than 10 years.  Good luck.  Here's a link from Texas A&M (TAMU) that you may find helpful.
Tom

http://aggie-horticulture.tamu.edu/archives/parsons/fruit/avocado2.html