If that's already got nutrients...you might regret it...It not a formula developed to give our plants the necessary %'s...

But, If you must...use it, just don't get caught up in overferting. wait until the plants show you they are lacking something. watch for the signs. good luck. you should look into some foxfarm soil
if you can afford it. It is pricy compared to other soil, but people who use it love it and grow get some real nice harvests...peace