TRANSPLANT TRANSPLANT TRANSPLANT. done properly it will not stress the plant at all. 1 1/2 gal is 2 small 2 flower imo. i always finished in 5gals, and a few times i finished in 3gals with a noticably smaller yeild. people on this forum seem to think transplanting is bad. that is totally untrue. your grow will be much better if you transplant 3-4 times instead of starting and finishing in the same pot. my 1st grow i transplanted 1 time. ever since i transplanted at least 3 times usually 4 times and the root systems were much bigger/healthier for it. as long as you don't manhandle the plant/roots while transplanting and use something with a little b1 like thrive alive there will be no stressing the plant. it is much more stressfull imo to have a rootbound plant or a seedling sitting in 5gal of sopping wet soil for 5-6 days till it can dry out thoroughly. mj hates wet feet! i like it to take no more than 3 days for the soil to dry out no matter what size pot it's in. good luck.