The unit, thought to be worth €1 billion to €2 billion ($1.24 billion to $2.49 billion), might attract bids from private equity firms such as Cinven Ltd, EQT Partners and Triton Advisers, Bloomberg said, citing people familiar with the matter.
Credit Suisse Group AG is advising Bayer on the potential sale, Bloomberg reported the sources as saying.
Bayer, which also plans to list its plastics unit on the stock market, is interested in bidding for animal-health company Zoetis, Bloomberg also reported.
Firms such as KKR, Advent and Carlyle Group looked at the plastics business after Bayer announced plans to spin off the division through a stock market listing.
Bayer, Credit Suisse, Cinven, EQT and Triton could not be reached immediately for comments outside regular business hours.