First post IE: Go easy on me.

When you taste a wine, how do you know if it such that the wine will improve with age?

I read all sorts of post, that state things like "this wine will reach it's peak from 2012-2015.

How do you know that?

Experience. Lots and lots of drinking, taking notes and more drinking. Seeing your own wines evolve. More drinking.

For the most part, many of us rely on the advice of experts when it comes to wines we are less familiar with.

Welcome aboard!

PH

When tasted young the wine should have no faults.
A good presence of acidity, tannins and sweetness. With well pronounced tannins and acidity, which are needed to be able to ripen. Don't mix up vegetal bitterness with tannins and prefer smooth tasty tannins on green, unpleasant tannins.

T'is a start.

Wines with higher acidity and tannins are usually the best to age. It depends on so many factors though so the best way to find out is to just try it

Acidity, tannins and fruit along with tasting at various stages of cellaring!