The picture..

{{gwi:1050891}}

What is the soil it's in and hows the drainage? Are you basing the watering just on temperature or do you check the soil b-4 watering? Tennis balls for aeration? ;-)

tj

Normal soil with volcanic rocks underneath. No drainage. I water it depending on how dry the soil is. I admit I am not a big expert on plants, so any extra help appreciated

Gee, maybe it's the tennis ball to be blamed ! :)

Cheers

Containers must have drainage.
Containers should be filled with potting mix, not soil.

the leaf tips show chronic water stress.

Agreed.
Browned leaf-tips usually indicate that root-death has occurred, typically from over-saturated soil.

Drainage is essential.

Josh

Oh, I neglected to mention:
Coarse stuff (such as volcanic rocks) in the bottom DOES NOT improve drainage.

Sad but true.

I will try the above, many thanks for all the responses!
Sofia