What I was thinking is creating some cards that you could give as a gift.
Here is what you do. Find local historic sites in your township or local area. Take a picture of it and create a blank card. It could be used by your customer in many ways.
Then package a half a dozen or so cards and envelopes in a larger envelope, with a customer appreciation letter.
The customer letter could say Thank you for choosing us to provide you
top notch lawn care service. To show our appreciation, we have enclosed these cards which feature images of local historic landmarks. Use them to reach out to friends and family. It will show them some of the landmarks that make our town unique. These photos were taken by Joe Smith, who is an avid
photographer. Thank you again for choosing us.
Sincerely, Joe Smith
You could also give these out to your all your customers at different times of the year. During the holidays you could take photos of Holiday decorations around the town.