So long as you don't take too many at once, and you space out your cloning sessions by at the very least two weeks, you should be able to hold on to one forever, as far as genetic/hormonal imprint, so long as you keep your mothers at optimum health, the clones will be at optimum health as well. The do take well to Superthrive, and Thrive Alive B1 after a cloning session, better not to nute the momma before a cloning session as well. If you let pests get to mother plants after a cloning session, the mothers health will rapidly decline. I usually keep my mothers for up to three years or 500 clones which ever comes first. You can also flower mother plants after you have taken the amount of clones you like (best to keep it under 200 if your going to flower them) and get about the same quality smoke, you just have to let it heal completely from the cloning before letting them flower. I usually give them nutrients almost exactly 36 hours before a cloning session...... other than that I don't know, unless my short term made me forget......