The land where the blueberries are grown must be free of prohibited substances (no synthetic pesticides, herbicides, or fungicides, no synthetic fertilizers, and no genetically engineered crops) for at least 3 years prior to the first harvest of organic blueberries. If you are purchasing new planting stock, you need to try to source organic plants. If organic blueberry plants are not commercially available, then you can use conventionally grown plants, but they must be managed organically for one year prior to harvest of organic fruit. You will need to establish a fertility management system that uses approved inputs and take steps to prevent soil erosion and contamination from adjoining land uses. You need to keep records of all of you farm activities and transactions and set up a method to track sales. You will need to complete an Organic System Plan (OSP) and have the plan approved by a USDA-accredited certification agency, after your farm has been inspected. You should contact a certification agency soon, request an OSP form, and begin the process. For further information there are many useful articles on organic certification posted here, An Introduction to Organic Certfiication Requirements.