Bloom calendar
Plants for Zone 4 That Bloom in September
307 plants in the BloomsEye library that are hardy in USDA hardiness zone 4 and typically flower in September, such as Switchgrass, Toad Lily and Aster. Each entry lists its bloom times, hardiness zones, and sun needs.
Showing 1 to 60 of 307 plants
How this list is made
Derived from each plant's bloom months and USDA hardiness zones, as stored in the BloomsEye library, which was written with AI assistance. Of these 307 plants, 266 have been checked against outside sources (16 fully verified); the rest have not been checked yet, and each plant's own page says which. The cards are AI-generated illustrations. Months here are Northern Hemisphere months; in the Southern Hemisphere, shift them by six months.
The flowers of September in zone 4
Every plant on this page is in flower in September. These are the ones with the shortest seasons around it, ranked by how much of each plant's flowering falls in August, September and October: a plant that opens and finishes here sits ahead of one that flowers from spring to frost, and ties go to the plants this site's guides name most often.
September bloom in zone 4 by flower color
A plant that comes in more than one color is counted under each. The picks rank the same way as the flowers above, so each color names the plants whose season sits closest to September.
September bloom in zone 4 for shade
30 of these 307 plants will flower in less than a full day of sun.
September bloom in zone 4 by height
Mature height, in the three bands a border is planted in. Anything over 10 ft is structure rather than a border plant, and a climber is sized by whatever it is growing up, so both sit this out.
Front of the border
under 12 in
10 plants
Middle of the border
12 in to 3 ft
176 plants
Back of the border
3 ft and up
93 plants
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Design your garden
Drop plants onto a 3D plan, see how they fill in, and watch the whole garden bloom across the year.