If Taric targets himself with Imbue, he'll be healed for more. As a result, he's very effective at tanking turrets.
Sometimes it's better to not use Shatter and keep the self Armor bonus.
Taric has very high armor due to his Shatter ability, and therefore casters are able to damage him much easier than physical fighters.
Make note of what summoner spells Taric has. If he has Clarity, it might be futile to harass him with spells early.