Hey there,
When autumn comes around and the world begins to anticipate decorating for Halloween and drinking the first PSL (Pumpkin Spiced Latte!) of the season, we usually don't think about what bees may bee foraging on.
In the central valley of California, flower season is beginning to slow down, but our honeybees are still able to gather nectar and pollen from the following floral sources:
Safflowers
Safflowers have a high concentration of pollen that the bees can't get enough of!
Source: http://safflowerseedsoil.org/safflower-plant/
Bee Balm
Bee Balm flowers can re-bloom when trimmed back in late summer
Source: https://www.almanac.com/plant/bee-balm
Sunflowers
Bees love sunflowers, and honeybees are often used to pollinate sunflowers for seeds
Goldenrod
Pro Tip: There are varieties of Goldenrod that are native to North America - search for these when planting!
Source: https://commons.wikimedia.org/wiki/File:Bee_and_Goldenrod.jpg
Purple Aster
Also native to parts of North America, you can often find Purple Aster growing wild with goldenrod flowers.
Source: https://www.almanac.com/plant/asters