D.C. Mun. Regs. tit. 9 § 473
Landscaping is the activity of arranging or modifying an area of land or natural scenery, by planting, removing or replacing plant life or by altering the contours of the ground. The services of landscaping and landscape construction, design, and architecture are taxable. Examples of services subject to tax under landscaping include, but are not limited to, the following:
Further examples of services which are taxable when performed under a landscaping contract include the following:
Vendors providing landscaping services or performing landscaping contracts may issue a resale certificate on all tangible personal property that will be sold or transferred as part of the taxable service or taxable contract.
For example, a landscape contractor who purchases trees and shrubs for installation may issue a resale certificate for those materials.
Vendors providing temporary help to perform landscaping services shall be required to collect the sales tax on the charges for that service. The tax shall be collected even if the temporary help performs some inconsequential nontaxable services. However, vendors providing temporary help for nontaxable services shall not be required to collect the tax if that help also performs some inconsequential taxable landscaping services.
D.C. Mun. Regs. Tit. 9, § 473