Mint will tolerate a wide range of conditions, including heavy soil. It prefers the wet and loves a bit of shade. With the rise in popularity over the past 20 years of Asian cuisine, many varieties of Asian mint have become popular, particularly Vietnamese mint. This is not strictly speaking a mint, as it is not actually part of the mentha family, but is instead is botanically known as Persicaria odorata (and sometimes, oddly, called Vietnamese coriander). Persicaria odorata is a little more temperamental than the common mint. It still enjoys shade and plenty of moisture, but it prefers freer draining soils and subtropical or tropical conditions. If you have a propagation house and are diligent with your watering you will find it will winter-over, but in the outdoor garden it is more of a perennial.
Both common garden mint and the Vietnamese varieties have lovely flowers, which, as well as the leaves, can be used in cooking. Since common mint is a cousin of the lavender, this should not be surprising, even if it enjoys almost completely the opposite growing conditions from lavender.
As a companion plant mint is hard to beat, unless you happen to be a parsley bush (again, there's always one), in which case you and mint will rub each other up the wrong way. This is because they have competing root systems that don't like each other. As a rule though, one - usually mint - will suppress the other.
In a cocktail, in a salad and in the classic mint sauce, fresh mint is a completely different proposition to its dried counterpart.
So, if you want to keep your mint "minty" for winter, freeze it with water in an ice cube tray. Save the dry stuff for rubbing on your lamb roast.