hey there Justlearning, PK is a great thing to have on hand. Thing is , there's no set time for it. Good news is that it's easy to time it. Just wait until the buds are the size of your thumb first, then add it to the feed at half dose, then gradually increase the dose until full dose or the flush . Hope this helps ! 🚀 you can check my diaries to see for yourself. Hope this helps ! 🚀