Potash levels extremely low throughout.

Doing soil tests on our plants last night and we discovered that our Potash levels on all plants are extremely low. I'm using Tiger Farm Grow Big, Tiger Bloom and Big Blossom, with Open Sesame Bud Setter. All our stems on our plants are turning (turned) purple. Its not a temperature and our PH is practically perfect. Are there potash stakes out there? Ya know like the Nitro sticks I see at all the nurseries for trees?. Or does this purple look like it should be there? PH is 6.9, we're in soil, and our temp is usually 76-78, 55% humidity, under a 1000Wt Merc Vap bulb.

add ashes from wood fires for more potash. sprinkle a little on the top soil and ad a little water to get it to sink in