Metaphor in the garden

Wisteria and the falling down structures:

There are 2 outbuildings, side by side. They are falling apart, heading downwards, bits of wood are falling off them, their roofs are at the wrong angles and the uprights are tilting severely.

The wisteria tree has been there for many years, it has a huge solid trunk and massive branches which spread right over the unstable structures. Even though it looks about to collapse I give it a shake, hoping it will crash around my ears, but it is surprisingly and annoyingly unbudgable. There are nasty sharp nails exposed by the falling planks. There are bits of wood at eye level which could damage anyone getting too close. It looks disturbing. It is disturbing. It is crashing down at a glacial pace.

Under each of these structures there is space for garden chairs. One is bigger and provides total protection from the rain, but is dusty and nothing grows under it. The other is smaller and lets the rain through, but has vines and wisteria leaves as its roof and is beautiful, cool when it is too hot, lets in a bit of sunlight and has an array of plants in pots from another part of the garden. Exiles from the dangerous wall which was taken down and rebuilt safely.

What can I do with my metaphor? What can I do with my garden?