Day Lillies are extremely tolerant and very strong. Perfect for growing near a sea front and for on windy sites.

Hardyness zones are an indication for the average lowest temperature in a specific area.
Almost all bulbs do well in US zones, but some bulbs need special treatment in extreme heat or cold area's.

Take your zone into account when buying bulbs but be aware that your zone is an indication and that specific situations in your garden can create micro climates that deviate from the hardyness indicated.