Mail out colorful brochures to the Admin Assistants at large corporations. Address them to : Administrative Assistant, Sales Dept (and Marketing, HR, Finance, etc).

Years ago when I worked at a major telecommunications company I started using a local cookie bouquet shop and a local bakery for all different occasions. Soon, all the different departments started using these same businesses and those little businesses flourished.

Taking actual bouquets, as previously suggested is great too. But that could get costly for you and it would be difficult to get to each department of a large corporation. But that idea would be great for smaller companies.