I’m on the mornington peninsula in Victoria and have killed every frangipani I’ve had. This time I’m determined. The frost has started so I’ve bought a little cheap greenhouse from Bunnings and put it in that but also put it on our sunniest wall next to our hot water heater to hopefully create some humidity. Luckily also, this position happens to be in front of our toilet window so I can still keep a really good eye on it! It seems to be working so far and it’s dropped to 2 degrees some mornings. I also just read on another page to surround it with rocks. The rocks, when hit with the sun retain the heat and keep it a bit warmer. So I’ll be doing that today!! It’s leaves are going a little bit yellow, does that mean it needs a fertiliser? I’ve lost maybe 4 so far but still seem to be getting the little new growth in the middle, I figure they are good signs?

One point against Native Frangipani is they are brittle and easily wind damaged. Only last weekend I had to remove 2 trees because the wind completly removed the branches from one side of the tree and the second tree split down the middle. This is fairly common with rainforest trees as they are generally shallow rooted and do require the rest of the forest for protection. I have also found too much mulch stops the tree from sending its roots down, The roots stay just under the surface where all the nutrients are. Plant them in a protected position and they should be OK. If planted in the shade the tree will be tall and straggley because it is trying to get to the sun as most rainforest trees have their canopies in the sun. If you plant rainforest trees in full sun they tend to be bushier and only grow to about 1/3 to 1/2 the stated forest height. A good example of this is the Flindersia brayleyana or Qld Maple. In the forest it may reach 40 metres but in full sun only 8 to 10 metres.

Does it happen at any particular time of year, or is it happening all the time? And what type of soil is in the planters? Don't know what you mean by "... noticed one tip to actually have sap as well ...". All parts of the plant should have sap.

C9, I would also wait until early spring. No sense doing it now unless you need to cover or protect the trees. Some cultivars (mostly rainbows in my experience) have die back issues from a cut in late fall or early winter. There is some good information on this forum about pruning techniques that may also be of assistance to you. Plumeria branches will generate from the leaf node scars nearest the cut. It's total luck of the draw how many branches you may get. I try to make my cuts along an axis that near as many leaf node scars a possible. I also use a pruning saw rather than shears.