If you aren't going to sell online nationally, only advertise in your local service area and do it on popular local internet businesses like the newspaper etc, sites where the local populace can see your listing or link to your web site.
Otherwise you will waste your time and possibly some bucks advertising to people out of your area. If you want online sales out of your area, you need some serious SEO (search engine optimization) which is very pricey and iffy as to returns. Otherwise, find a forum or forums that talk about landscaping and volunteer your time and knowledge answering posts; if you're good, you'll build a following and if you can follow through with sales and keep a good reputation, off ya go to new heights.
There should be a Google Group for landscaping.
IIRC,
www.yellowpages.com might help, and there are others that are natioanl and local, but I can't recall the names.
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