Prunus
Plum trees have roots that are mostly 12 inches to 18 inches deep and go to the drip line. A few of the roots will go about five feet down to anchor the tree.
Victoria plums are self fertile so do not require another plum tree to pollinate them.
it could
Two to three years if you get a nursery tree. If you plant a seed, then it will take 4-5.
This could be a reaction to the tree's roots having too little, or too much water.On newly-planted trees, you could try elevating it a bit or providing additional drainage.Normally, a deciduous plum will only lose foliage in the winter.
You dig a hole and put the plum tree into it.
wood land
Most conifer roots are fibrous and do not make heavy roots that would cause a problem.
In a plum tree.
It may be aphids.https://www.gardeningknowhow.com/edible/fruits/plum/common-plum-tree-pests.htm
spraying a plum tree with what? against what pest/disease?