How does plant structure affect yield?

[plantingplants]

If all other variables are mostly equal, how can a big plant only yield two lbs and get outyielded by a small plant? Is it just number of tops? How do you make a big plant that has fewer tops create more through lst like pulling through a trellis?

I have some plants that get bushy with short internodal space, and some plants that get tall and lanky. I kinda just let nature do its thing but pull beqnches sideways through trellis but idk what else to do. Really i am stumped in general on the topic and i feel like my yield suffers because my lack of knowledge..

Any help is greatly appreciated!

 

[Ibechillin]

Number of tops/bud sites and removal of shaded inner nodes seem to be the main correlation in reference to yield from what ive gathered.

I usually wait to do any pruning until the plants are well-established in their final homes. This year we did the first round of pruning about a month ago, at the beginning of june, about 3 months after germination and 1 month after transplanting. They will need it again sometime this month, and possibly once more as they enter flowering.

We do a pretty extensive pruning of all the inner branches and growth tips, even small ones. Not the fan-leaves though. Tom Hill called this the "pistil-whip" technique. Some strains require more aggressive pruning while some require very little. The goal is to clean out all the growth that will not receive light, or cannot support itself.

It's kind of strain dependent but usually each main branch gets the first 3-4 shoots pruned off... more on the lowers and less on the middle branches. the top of the plant stays untouched always, pretty much.

 

[plantingplants]

Thanks IBC. I had been following shcrews' advice of not topping but i think that works for him because he gets such great growth and his plants just fill out. i definitely have some plants with a lot of height but not many tops. Is it too late to top?

 

[steasy88]

I think u could pinch the top head and it should let the side branches catch up with the top and bush out for you plus u get to keep the main cola as well not to Sure if u can still do it but if u have at least 3 weeks of veg left before the turn its do able all the best on it

 

[gorilla ganja]

Top the tallest shoots, supper crop,FIM, lst the top it all has the same effect.
Fools the plant into producing side branches instead of growing taller.

My favorite is lst. Simply bending the main top, or any branch that grows taller than the others down lower than the other tops. secure in place and watch side branches take off.

In the following pics I tied down the top for 2 weeks then went back and released it to grow natural. It is very low stress. And you can see the difference in branches in only 2 weeks.

To answer your question. It all boils down to bud sites. A "small plant" that is shorter but has twice the bud sites or nodes than a "large" taller plant will produce more in the end.
Hope this helps.

Peace GG

 

[Zarezhu]

Its quite simple really. It's not height that determines plant yield, but surface area of the canopy. If you have a short, but wide and bushy DOME shaped plant, your sq. ft of canopy recieving sunlight will be higher than simply a tall plant with major colas. You need to encourage the dome shape, as thesun is not a fixed light, and it moves in a 180 around the plant throughout the day.

 

[Ibechillin]

Planting in huge 1000 gallon mounds really lets the plant fill out on its own, i remember him saying the mounds were 10-12ft in diameter lol.

Heres an example on topping and time to recover from my blue cheese plant. Notice how open it is before.

Day 49 end week 7.
I topped all the main branch tops.

Front

Back

Front 10 days later, day 59

Back 14 days later, day 63

I plan on doing another round of topping this sunday 3 weeks after the first round. Then the plant will have about another 3 weeks to grow more side branches before stretch begins.

 

[steasy88]

Wow that is a big plant don't think I could hide that monster in my back garden have to keep them small how many time can u top a plant before it start to affect the quality of the nuggets or can u just keep topping to have multiple heads

 

[Ibechillin]

I dont think topping affects quality at all, just creates multiple smaller colas where you would of had one larger cola.

Throughout veg you can top quite often to keep creating more and more tops. I feel like the key to it is letting the new side branches fill in for 2 to 3 weeks before topping again so they have a chance to get some girth to them. You dont want a bunch of spindly side branches and spindly tops.

 

[plantingplants]

Thank you guys.

IBC, those photos help a lot-- i have a number of plants like that first photo. Some of my HSO Green Crack like to do that.

So it's tops. I need tops. This is simple.

 

[CrushnYuba]

I believe topping messes with the structure of a plant. Makes it hard to support with all the crazy branches. Much easier with one main stem that has main branches coming off. Especially using cages or vertical trellis.
Usually with enough sun they turn into round balls anyway. Some seed plants genetically just don't want to do it though. Almost all clones don't need to be topped. I do sometimes top but it's usually way late in the game. Good root space and not being crowded for sun early on before getting planted helps. Also Later on. Plants usually don't like growing to much wider then their roots.
Also i feel like having multiple main stalks compete with each other on the inside. Just like triple planting pots does.
Once the plant Is way Big, topping is cool because it breaks up those main colas.
Using trellis outdoors isn't to increase yield like In depps. Its to support branches and buds.


That being said, sometimes small plants are Really surprising. I think it's because the entire plant gets light.

 

[RosettaStoned]

More even tops = more yield generally. That's how indoor growers in micro cabs pull decent weights, scrogging and such. The only problem with topping is that it can stress the plant a bit, slowing your growth. Rather than topping multiple times, it may be more worth it to just do some gradual LST. Just training the top to be lower than the canopy so it all evens out really helps. I do this, then train the tops that become more dominant out, making way for even more tops to form, and I end up with a nice even bush.

 

[Farm Hero]

Don't forget a cage that properly supports topped plants really helps them reach full potential.

A plant isn't going to grow a bud any heavier than what the branch can support. A good cage makes it a non-issue

 

[St. Phatty]

I just finished bagging 2 dry plants.

One was a Bay Dream cross, with large Sativa leaning buds on an Indica branch structure, with not a lot of branches. 2 1/2 pounds dry with the stem.

The other was a Blueberry Headband cross, with very Indica buds on a Sativa branch structure - lots of stretching in the branches. 3 pounds dry with the stem.

It was hard to say upfront what outyields what.

For those who are preparing buds for the commercial market, manicuring time becomes important. Then you need fewer, bigger, super resiny buds. A long Flowering time helps in the yield per bud department and the Resin department.

The Bay Dream cross went 12 weeks of flowering. The Blueberry HB cross went 11 weeks. Outdoor flowering times.


Indoor flowering can be different because you're doing multiple cycles, whereas outdoor it's usually one per year. So outdoor a 12 week flowering time is OK, whereas indoors it's ringing up the power bill and consuming garden space.

 

[therevverend]

Plant structure is very important. I almost never top, feel like it slows growth at a critical time. It destabilizes the plant structure so when a storm hits the plant gets hammered. To me it's more critical to get the upper floral structures to put as much size as possible then to try to increase the number of them.
Without topping my goal is to select for plants with a structure that increases yield. Here's a picture of a plant with good structure for yield.

The top has a round shape, lots of main branches. Looks like it was topped but wasn't. A fairly common structure it is a waste to top because it already will produce plenty of main colas.
It's awesome for yield, although there are two problems. My female with that shape got hammered by a storm. The structure blocks off the light to the lower parts of the plant. Even if you remove a lot of the shade leaves you won't get much light inside. And if you remove the shade leaves you're removing energy from the tops which defeats the original purpose.
Here's a plant with an open structure that allows light to penetrate into the heart of the plant. The lowest limbs were almost lying on the ground and they had large colas. There were hardly any small scruffle buds on the plant.

I know a grower/breeder that prefers these kind of plants. His strains can put out 10 lbs a plant. Because it's one of my dinky little plants it won't get 1/10th of that..

 

[soil margin]

Wide plants yield much more than tall plants because the surface area capable of absorbing light increases much more when you for example, double the plant width as opposed to doubling it's height. So in general you want a wide root base and as wide/even a canopy as possible to maximize yield. Lots of tops that are spread out and not shading each other is nice to have as well.