The overall Mandate of the Directorate is to facilitate the development, promotion, coordination and regulation of the horticultural sub-sector in Kenya. The roles and responsibilities of the Directorate are to:

1. Advice the Government and the industry on matters related to horticulture production and marketing;
2. Collect and collate data, maintain a database and disseminate information on horticultural activities for planning purposes;
3. Provide specialized horticulture extension services;
4. Appoint agents for the implementation or performance of any function of the Authority under the mandate;
5. Directly or indirectly support the establishment of fruit tree mother blocks;
6. Regulate the horticulture nurseries, production, post-harvest handling and marketing of horticultural crops and produce;
7. Promote development and adoption of standards for labelling, packaging, grading, transporting and storing horticultural produce in compliance with local and international standards;
8. Impose levies, fees or charges on producers, dealers and nursery operators as the Minister may approve;
9. Promote the establishment and use of production, processing and marketing infrastructure for horticultural crops;
10. Facilitate marketing of horticultural products in the local and international markets; and
11. Provide for any other matter in furtherance of the development of horticultural crops  or conducive to the exercise of its mandate.