The Largest Selection of Landscaping Rocks in the Tampa Bay Area! Seffner Rock & Gravel has been serving the Tampa Bay area's landscaping supply needs for almost 23 years! In 1990, Seffner Rock & Gravel started with one delivery truck and a dedicated staff. As we begin our 24th year in business, we are excited to offer you the best selection and prices in the area, backed by our knowledgeable...