Purple Kush is an elite clone which means there are no seeds to be had. Reefermans early PK is crossed with an early girl strain to make the seed. I hear the results are unfavorable. You can find clones at SR-71 in Oaksterdam (downtown Oakland). It grows short and extremely bushy with giant fan leaves. I prune some of the middle and undergrowth out of mine a few weeks before flower to increase the airflow to avoid the powdery mildew issues i have had in the past. Make sure you have plenty of airflow. An extra week of flower will make for more purple color, flavor, and density. Don't expect much of a yield, but do expect tasty couch-locking nugs. Not sure if you can get it shipped to the US(legally) but here's a link that claims to have feminized seed, although every time I've visited they are always "sold out"
http://www.bcseedking.com