Hi all

My gorgeous frangipani appears sick.

It is in the ground in sandy soil doesnt drain/absorb all that well against the wall of a house facing NE. Just dug around in the soil and it is very dry.

Last year it bloomed beautifully lots of flowers and kept is leaves late into winter (in fact I don't think it ever didn't have leaves)

Got more foliage as summer started and I was sure I was in for a bumper crop but it never bloomed and despite the heat and my neglect the leaves started wilting.

Then I notice the soft stems. I worried it was rot and was advised to cut the soft stems away but when I did white sap came out. I thought that meant it was healthy.

Can anyone advise what to do? Should I pull it out of the ground and place in a pot?

Happy to add more pics if it helps

Well, your stems do look a little desiccated, the fact that when you cut them you got clean tissue and white sap means that they are seemingly healthy. Perhaps you might need to give it just a tad more water?
When we were in the Cayman Islands plumeria grew naturally there, by the side of the road. No one took care of them. What we thought would be a lush, jungly island with gingers, palms and heliconias everywhere was actually a rather barren nondescript landscape. The only places that had the lush vegetation we expected were resort hotels where the plants were taken care of (at great cost, because fresh water for irrigation is costly).
The plumeria there grew in basically rocky sandy scree as tropical succulents and the only water they got was what they could soak up when it rained. Maybe deep water your plant once a week? Or when you see the leaves wilting.

I'm thinking NE side of the house is the problem. I have had some problems with one of mine in that situation. It takes longer for the soil to warm and the sun to get to it in late winter/ early spring in my So. Cal site.