ACLU's site (ACLU of Washington | A Guide to Washington's Medical Marijuana Law) gives a link to the Department of Health (Medical Marijuana Frequently Asked Questions - Washington State Dept of Health) site's FAQ, It says:
"A qualifying patient or designated provider may have a 60-day supply of medical marijuana. A 60-day supply is defined as 24 ounces and 15 plants (WAC 246-75-010). The law says that a patient may exceed these limits if he or she can prove medical need." (about half way down the page)

I guess different states resident's need different amounts! Montana is 6 plants and one ounce.

Dennis, blurry eyed in Montana :hippy: