Autumn signals the start of the garden's slow saunter toward winter. Plants and gardeners alike welcome the return of cooler weather and lower humidity. It's a time when some flowering plants finally get exactly what they've been waiting for: the short days and cool temperatures that trigger asters, chrysanthemums, and goldenrods to cover themselves with blossoms. Here are some tips on adding late-blooming flowers and grasses so your garden is still colourful in the fall.