That's really a misconception. Autoflowers are incredivly resilient. My very first auto was a White Widow in DWC. at 21 days, I accidentally broke the stem at the second node! I taped her up and three days later her stem was healed enough to remove the tape. She stalled for about 10 days. I was growing two of these. The second one gave me 30 grams, the plant I broke? 170 grams! Had other really stressed autos,
( been growing them quite a while ), like the one myy dog pulled completely out of a pot of coco, about ten days old. I replanted it just for the hell of it, didn't expect it to live. Again, the biggest and best producer of the lot.
The trick with training them is start early.
I defoliated this girl about 2 weeks ago. Linda seeds Gorilla Glue auto in a 1 gallon ( 4L ) pot. 44" tall. She's so tall in that little pot I had to tie her to keep her from falling over.
she at about day 50 right now
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