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"i was wondering if there was any way to slow down plant growth vertically."
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I have Bushmaster that mrduke suggested, works as advertised but unless it's carried in a hydro shop near you it'll be too late by the time it comes in the mail. You can low stress train in flower. I've read about some people topping just before flower, I've never done it though - I would think it would reduce yield but haven't read anything on it.
And as Justin is leading too (I assume, sorry if I'm typing words with your fingers Justin), if you are using a low K light during veg you will get stretch (long internode distance) and if you use a high K light at the first of veg it will slow the transition into flower and your plants will be taller. An HPS is 2100K, promotes transition into flower. A 4000K - 10,000K light will keep the internode distance short during veg. I was using a 10,000K, 125W VHO florescent during flower and started using a 2100K 150W HPS last week when I built a new veg cabinet - my plants are stetching already, the older nodes are close and the newer nodes are spread.
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As the other guys suggested, topping and low stress training will help. I've grown 6'6" of stem 6" above the bucket rim. I use to lst when I transplanted into flower without a problem, you could bend them and leave them in flower or take them out and put them back in veg. Careful with LST, the stems will crease and snap by times.
I do CCOB, like an inefficient scrog without the screen. I top my plants once; veg each side of the stem to 22" in a 6" pot; transplant to a 5 gallon pot on an angle; bend the stems around the bucket rim. The branches grow up and the stem acts like a hydro tube feeding each small cola.
The stems virtually stop growing when they're bent horizontal, so I have to veg the plants so they will bend all the way around the 38" bucket rim. A single 38" stem is thicker and harder to train; two 22" stems crossed at the bottom and following the natural curve of a topped plant will train much quicker and easier.
This is a 1 stem Kali Mist at 35" and a 2 stem Flo (18" & 19"). The stem is much thicker and more difficult to bend and train. We need to get the stem around the 38" of the bucket rim to get as many branches as possible, so two thinner, shorter stems are much easier. The stems virtually stop growth and stretch when bent horizontal, many more branches than a vertical plant of the same stem length. The Flo trained in about 15 minutes and the Kali Mist took days.
Flo -
Kali Mist
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This Bubblegum's stems weren't crossed and took over a week to train. If crossed I could have done it in a few hours.
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Flo
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Kali Mist
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A Flo (left) and a Bubblegum. The Flo has another week or three, the Bubblegum should harvest in the next week. The Flo is a knarly plant, twisty leaves, small hard buds. This is my second time around for the Flo, the last hermied and I burnt it with Dutch Passion Penetrator. The smoke was so beautiful I had to run it again, this time just a few pre flower pods and bananas on the lower nodes. I picked them off and the plant has been perfect since.
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The Bubblegum (right) is going to be my best producer ever, of Bubblegum. I should get 12+ cups of cured bud.
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The single stem Kali Mist from above on the left; on the right a Kali Mist grown with 4" of height above the bucket rim.
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I've got some more pics of how I lst in this thread if you're interested.
Pics of my garden: SSD, KM, BG, BL, T, Flo, RD
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