Ask Mr. Smarty Plants

Our first thought was to say that couldn't be done. However, we are not as familiar with the growing habits of wildflowers in Illinois as we are those in Texas, and couldn't find anything right offhand that said "this seed shall be planted at this time, etc." We did find several excellent websites on Illinois wildflowers, to which we will give you links so you can do some further research on when and where to plant the flowers you want.

In our Native Plant Database, we can search for annual flowers (which would ordinarily be planted from seed) that bloom in September and October and select some that are attractive. The catch is, some of those that bloom that late in the year started blooming months earlier, like July, and the seeds may be so confused that they won't even germinate until next Spring, because that is when we would ordinarily recommend annual wildflowers be planted in your area of west central Illinois, USDA Hardiness Zones 5b to 6a.

It sounds like you already have a wildflower mix you want to plant, in which case the information we give you won't be of much use to you. If that is the situation, go ahead and plant them right now and see what happens. Read the instructions on the packet for planting in sun or shade, watering and so forth. It should also say on the package when to plant the seeds, and we bet it's early Spring. Or you can keep the seeds and plant them in early Spring, because we only found three Illinois wildflowers that bloom in September or October.

Illinois Wildflowers

University of Illinois Extension Wildflowers

Illinois Native Plant Society

Native Illinois Wildflowers That Bloom in September and October:

Chamaecrista fasciculata (partridge pea) - blooms yellow June to October

Oenothera rhombipetala (fourpoint evening-primrose) - blooms yellow May to September

Rudbeckia hirta (blackeyed Susan) - blooms yellow June to October