Hire a firm with a licensed Pesticide Applicator. If you have an insect, weed, or disease problem that requires treatment, the business providing that treatment must have a Certified Pesticide Applicator on staff. Certified by the State of Delaware, licensed pest applicators take a written exam and attend continuing education classes to maintain that certification.
Hire a certified Nutrient Handler to apply fertilizer. Professionals who apply fertilizer to more than 10 acres combined must be certified as nutrient management handlers through the Delaware Nutrient Management Commission. Recertification credits are required yearly.
Hire an arborist who has a certificate of insurance. No one anticipates problems, but a trustworthy arborist will have insurance to cover unexpected incidents or damage. Ask to see the certificate.
Be a responsible consumer. Ask questions. Make sure the person you hire is a licensed and insured professional. For guidance on hiring a Lawn and Landscape Company, see the following publication on the University of Delaware Cooperative Extension Website.