Posted: 19/02/2016 at 10:11
It is natural for evergreen plants to shed leaves but in small doses as they renew themselves. If it does it in large quantities something is wrong.
Mine is bigger and did this about a year ago and I concluded it was starving. It is now healthy again and gorgeous. I keep its pot on a wheeled base now to make it movable for occasional turning and cleaning under and around it.
This is what worked for me. Lift it out of its pot and soak the rootball thoroughly in a big bucket until no further bubbles appear.
Then tease out some of the roots so they stop going round and round and will be more likely to grow outwards then re pot in a bigger pot with fresh compost. Top dress with compost to cover those roots by about 1 or 2cms. Water thoroughly but let it drain before returning to its position.
Water regularly and give a weekly liquid feed from spring through to mid summer or push in some of those slow release feed sticks for leafy houseplants. Turn it occasionally to balance growth towards the light.
If you don't want it to grow much bigger, you'll need to trim some of the roots off before re-potting in the same pot. It will still need feeding and watering to keep it healthy.