I think the plant may have suffered frostbite. It has always been an outside plant and survived the Houston winters but after a freeze this winter the leaves turned yellow/brown and the top is hard with no growth. Can anything be done to save this plant...It is more than 30 years old. Thank you.
Check the bulb base. Is is firm or does it appear soft>
If it suffered damage, it can rot and it may not recover.
Give it some time and see if new growth appears.