I wouldnt recomend topping an auto... however if you do you should see some growth within a week. My topped plant took off on a growth spurt soon after topping her but it doesnt look like she will yield as much as my lstd plants. They all have several tops all over that are way bigger... my topped girl has four tops but not as big. However i did top her above the second node. Is ther a reason as to y u want to top her?