How Often Should You Fertilize Perennials, Shrubs, And Trees? For most established perennials, shrubs, and trees, you can fertilize with slow-release granular fertilizer once a year in late winter to ...
If you like zinnias and dahlias, then perennial mums are absolutely going to float your boat. They’re a little harder to find, so you want to be sure you’re asking for perennial mums.