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Defoliation

I had the thought that perhaps over defoliation during flower will stress the plant but I’m seeing lots of that going on here with no issues. I’ve just thinned out the single one I’ve just started flowering. I have to be careful or I can go a little extreme. I get so that I want the big leaves off so the wee leaves can grow. But … am I removing her ability to feed herself by doing this?

Things that make ya go hmmm… :slight_smile:

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Back in the day, when I was growing, I did defoliate with good results. The results got even better when I added 4 foot 2 tube fluorescent lights (with reflectors) along the sides of the plants, mounted facing into the plants thus lighting the lower center of the plants. In other words, if you have 4 foot plants, the fluorescents would be mounted 2 feet down from the tops. From the photos I have seen here, no one is doing that. Give it a try. I think you’ll like the results.

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There are some prototypes I’ve seen of under lighting specifically for this, it’s an interesting idea.

Have you ever seen GrowFilm before? It’s mylar thin-film with LED’s running through them, flexible. I want to try making cylindrical tubes and putting them around branches as a test lol.

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That could open up a whole new world of interesting possibilities if its gentle enough to not burn but strong enough to grow solid flowers. From there you could plan a plant out long in advance with some mainlining and have tube after tube of these reflective led cylinders giving grade A product. Fun idea that needs experimentation I think.

I also wanted to share this photo. Getting overzealous with defoliation you can see where this part of the plant completely stopped growing and avoided the area where that leaf was removed from.

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The fluorescents I used were cheap and did not put out much heat.

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I love this suggestion! We lose so much light from a single overhead source thanks to the inverse square law. One may to mitigate that problem is to provide supplemental lighting through side lighting.

If you want to increase some cannabinoid content in your flowers, try adding some UVB lights into those reflectors. Anything above 6500° Kelvin should suffice, but get up to that 10,000° Kelvin and your plants will exhibit a stress-activated response that should increase terpene and THC levels. Hortilux makes a PowerVeg bulb that hits all the right spectral notes and fits right into a traditional T5 fixture.

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How close do you suggest UVB bulbs should be compared to other light sources? I’ve seen growers use reptile bulbs and things to that effect in conjunction with LED panels or other even other HID lights, was just curious if there is a recommended distance from the canopy to provide maximum effect depending on the source of the UVB?

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I have a test that I always do with every lighting source I use (it’s very un-scientific, but it works): I put my hand up right under the light source. As soon as I feel the heat from the lamp against my skin, I know this is the minimum distance to the light my canopy should be allowed to grow. T5s and T8s don’t put off very much heat, so I find my plants can grow very close to these lights with no adverse affects.

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I actually do and advise growers to do the same thing lol. :laughing:

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Are these all the same strain? Certain strains may respond to this treatment, but this evidence should not suggest that defoliation will improve flower yields for all, or even most, strains.

More importantly, defoliation takes time, and time is money. Does this treatment even result in increased yield enough to justify it at $1/gram wholesale and $10/hour for the labor, even for this strain?

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I also disagree with this practice on an economic basis. It is time consuming, and while lower flowers do become more marketable, I think top flowers do not reach their full potential. I think yield is a wash, at best. Back in my dried flower and hash making days, all those small buds just went to hash anyway.

I do understand markets. If you are still getting top dollar for flower and your hash market hasn’t taken off yet, maximizing marketable flower is what you should do. If your cost-benefit analysis shows a profit, keep it up. At the same time, when markets begin to swing against the grower, and they will, be prepared to reevaluate your systems and don’t fear change.

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Here’s another article on defoliation.

http://spliffseeds.cmun.it/e/moyvxl/defoliation-and-pruning-cannabis-plants-for-maximum-yields.html?t=1526002194

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To quote the article, “Defoliation during flowering is a bit more controversial, as stunting a cannabis plant anywhere in this 8-12 week window will probably affect the yield.”

Defoliating for air flow and top grow is one thing, complete defoliation during flower is another.

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Also, lopping tomatoes is more akin to super cropping, not defoliation. This is a poor analogy.

Legit, zero data to prove anything. At least the main guy being interviewed admits that it is his opinion.

I’ve done both, I don’t see any benefit for my time. Trimming large leaves is much easier when the plant is down. I don’t believe that it helps with trim time in the overall sense, since you are trimming throughout flower, just more slowly.

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I am on the defoliation train now. The room I was doing full test on yielded 52 pounds with only 2% smalls(any bud that falls through 1/4" screen). We normally average 30-40 pounds with 7-9% smalls. the next 2 rooms look like they will be a larger yield. I am noticing that different strains do require different times for full defoliation. I encourage people to experiment to find their strain “sweet spot” times to defoliate . As for the added labor, our sprays are more effective, take less time to apply, and we are using much less. Our harvest times are also decreasing.I have not ran the numbers but, those two things should average out the cost of time it takes to yank those leaves.
With this method I am currently getting 2.75 pounds per light, more fine tuning, I believe, will take us over the 3 pound a light hump easily. First pic is week 4 , other 2 are week 7

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I think this all comes down to personal preference. I’ve worked with many people who love defoliation, but probably just as many that don’t. It’s all about what works in your garden.

With costs of pesticides/fungicides/insecticides rising, and the amount getting sprayed at a time, defoliation is a great way to save cost. You can save up to 50% or more product depending on how heavy you go on defoliation.

I definitely see both sides, and it just depends on your system in the end.

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Nope, nothing changed expect the defoliation. I have done 3 rooms in comparison with exact same strain, in exact same room.we did side by sides ( 10 lights control 10 lights test with the same 3 crops until this last harvest).
I believe it comes down to knowing when to defoliate after seeing these results. IMHO I see this becoming an industry standard soon.
We don’t spray flowers either, just up to week 5 or as soon as we see significant amount of pistols.

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I 100% agree, some setups might not do well with defoliating.

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Actually, it’s gone the other way in our open rec market. It was a huge fad for awhile here. Some small grows and med swear by it, but you go looking up large farms today, indoor and out, and you don’t really see defoliation anymore.

Perhaps it just boils down to being regulated by plant count vs plant canopy in square feet?

There are much fewer craps to give when you are regulated by plant area rather than plant count.

For example, people wanted 5 pound plants in med grows regulated by plant count. Makes sense, but I can grow 5 smaller plants for cheaper than 1 giant plant in the same area. I absolutely do not want 5lb plants. That just means more work. 1lb to 1.5lb plants are ideal from a throughput perspective.

As your market begins to flood in you area, be prepared to adjust your paradigm. Lowest cost wins every time.

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In the CO market, we are limited by plant count. Most grows I’ve seen however, it’s not really a limitation. Many grows have adapted and are implementing perpetual harvest models to keep production in par.

I’ve only seen a couple outdoor farms actually defoliate “heavy-ish”. It’s not such a big deal outdoor (more airflow, more light, etc), plus it’s a huge job to try to get done in a timely manner.

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