Other Options: Register for access to the Pennsylvania Department of Agriculture PaPlants website using your PaPlants ID and PIN numbers. Forgot your Password? Name: You can search by the merchant's full name (e.g. A Z Nursery Co.) or by a partial name using the * symbol (e.g. *nursery* or A*) Controlled Plants. Hemp - Cannabis sativa L and any viable part of that plant with a delta-9 THC concentration of not more than 0.3% on a dry weight basis. Questions regarding the control programs should be directed to the contact listed below or the nearest PDA Regional Office. Vote in the 2021 PDA Board of Directors Election. Now is the time to vote for three board members who will take seats on PDA’s Board of Directors in 2021. Learn more about the candidates and cast your vote by Nov. 15. Download pdf: The role of potash in plants (167.08K) pdf 167.08K. The role of potash in plants. May 2015. Ian Matts, Company Agronomist, Yara UK. Potassium is one of the major nutrients required by all crops and is present in large quantities in the plant in the form of the cation K+ PDA Plants is here to provide trustworthy and reliable sourcing solutions for hemp processors of any scale. With a wide range of products, we are confident we can fit your unique processing needs. PDA is proud to offer CERTIFIED ORGANIC material this coming harvest season.