Pansies are cool-season annuals. It's normal for them to fade and look scraggly as weather warms when summer approaches. In cool climates you can often keep them alive through summer months and they'll return with bloom in the fall. However, where summers are long and hot, it's best to remove them when they fade in spring and replace them with more heat-tolerant flowers for summer. When cool weather returns in fall, you can replant pansies for good color in fall and spring.