Possibly! If the recognition holder's healthcare practitioner determines the patient requires more than 6 plants, they may indicate on the authorization form allowance of up to 15 plants for personal medical use In this case, the patient may possess 16 ounces of usable cannabis produced from their plants.
No more than 15 plants may be grown or located in a housing unit even if multiple qualifying patients or designated providers reside in the housing unit. The only exception is for a registered cooperative defined under RCW 69.51A.25