Hi John,
Considering I don't know where you are in terms of site development, I will offer some suggestions in general terms.
1. Do you keyword research to determine how your customers will find you. Include your city and/or state name in your searches. Build pages that your customers will find beneficial and optimize for those.
2. Use your city name and/or state in title tags and on page where appropriate.
3. Make sure you use your local area code, zip code, street address consistently in all your local directories and Google Places. Visit getlisted.org for directory submission ideas.
4. Put your address in the footer of your site.
5. A blog is a great idea for lawn seasonal lawn care tips. Take photos/videos of your work and post them on your site/blog to beef up content. Example: "Here's what we can do about chick weed starting to show during the winter months." - I called my lawn guy about it last week :).
6. Leverage social media (Facebook specifically) for connecting your customers and allowing your customers to share with friends.
7. I wouldn't have one picture on my site that was not a local picture. Name your files with localized tags and use proper alt tags.
8. Its okay to include surrounding communities in titles, meta descriptions and on-page etc. as Google will pick those up as well depending on the competition.
9. If you have relationships with local vendors ask them for a link.
10. Don't do more for your site than you can effectively manage. If you can't keep your site, blog, facebook page etc. fresh, don't do it. Scale it back, keep it simple and ALWAYS keep your customer's benefit the motivation for what you do.
Good luck!