LED in veg observations

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I veg for 2 weeks, and switched from a 400w metal halide to 240w 3500k QB (no red) in veg a few cycles ago. What I'm seeing is increased lateral branching, where the side branches grow to compete and match with the main stem. Generally a positive if you're a 'Bush style' grower, but I grow 5-10 spears/towers. So only the main tops.

There's no question the LED is way more efficient in par/watt, but I do like the growth habit I get from MH.
Before I switch back to MH I will try dimming the LED all the way down for a couple cycles and see what effect that has, to test if less intensity discourages so much lateral growth.

Anyone else care to share LED growth habit observations?

 

[Creeperpark]

If you keep the LEDs close to the plants during veg. you will get increased lateral branching. However if you back the lights off and extend the space between the plants and LEDs you can achieve the spears/towers with trellis. The canopy intensity can be adjusted to suit your grow needs with raising the lights by trial and error. The major plus with LEDs is heat reduction and lower electricity costs as you know. There are plus's and minus's with both types of lighting when used by themselves.

When I use HPS with LED together in the same grow with a mixed light spectrum the growth is explosive. I've never seen anything like it, when it comes to plant productivity, bud density and speed of the grow. If you can manage the heat and can put both lights in the same grow area, the plants will grow faster and bigger than they can do outdoors. I use this method mostly as a Winter grow only because of the heat, but you can harvest the heat in the Winter off the grow and heat the home.

 

[BobChronic6505]

I never could get mature enough trichomes when flowering with LED. Clear ass trikes 10 weeks in flower. Still pisses me off.

They seem ok to start seeds and veg with tho.

I have been doing the SOG, single top spear style grows you talk about. I do it with an hps and 12/12 from seed. I cut off all branches I like it I feel like I can fit more plants in a smaller space that way. I have probs with mold tho. I almost wonder if buds are getting too big for their own good this way. I worry about air flow in those dense congested bud sites up top. Anything you can offer as far as that goes?

 

[.............]

I never could get mature enough trichomes when flowering with LED. Clear ass trikes 10 weeks in flower. Still pisses me off.

They seem ok to start seeds and veg with tho.

I have been doing the SOG, single top spear style grows you talk about. I do it with an hps and 12/12 from seed. I cut off all branches I like it I feel like I can fit more plants in a smaller space that way. I have probs with mold tho. I almost wonder if buds are getting too big for their own good this way. I worry about air flow in those dense congested bud sites up top. Anything you can offer as far as that goes?

I do 5-10 tops per plant. I use to do SOG though but the amount of work running a sog perpetual is alot and I yield more with larger plants.
Whats your humidity level? Let's make a an anti bud rot list:
-Dehumidifier
-Air flow (fans/oscillating fans above and below the canopy
-Silica (I use Power SI
-Strain selection, some strains are more susceptible, plus taking into account bud structure.
-Managing the dew point at lights off.
-Managing temps in relation to humidity, higher humidity=higher temps.
-Managing the harvest window to avoid bud rot, 1 week can make a big difference.
-Leaf stripping/defoliation. Non negotiable in my circumstances otherwise I'd have alot of rot.

I think plants under LED can be more susceptible to budrot because HPS is warmer and drier around the tops, obviously everything is the same in the dark period. Except for LED gardens cooling down much faster at lights off.

 

[.............]

If you keep the LEDs close to the plants during veg. you will get increased lateral branching. However if you back the lights off and extend the space between the plants and LEDs you can achieve the spears/towers with trellis. The canopy intensity can be adjusted to suit your grow needs with raising the lights by trial and error. The major plus with LEDs is heat reduction and lower electricity costs as you know. There are plus's and minus's with both types of lighting when used by themselves.

When I use HPS with LED together in the same grow with a mixed light spectrum the growth is explosive. I've never seen anything like it, when it comes to plant productivity, bud density and speed of the grow. If you can manage the heat and can put both lights in the same grow area, the plants will grow faster and bigger than they can do outdoors. I use this method mostly as a Winter grow only because of the heat, but you can harvest the heat in the Winter off the grow and heat the home.

Yo creeper thanks for the reply, and confirming what I'm thinking.
I guess dimming/backing off the par will get the same result as raising the LED. (Its already as high as it will go).
I use a lux meter so I can be very precise if I want. Under the MH I averaged 400 PAR over the canopy in veg, but the LED at the same PAR is too intense.

In flower Ive ran many cycles of qb led and 1k HPS combo. I eventually changed out the HID for another LED. As you say they both have their strengths and weaknesses, agreed.

At this point I'm going to switch back to MH. I just don't like what I'm seeing. As far as yields from the LED veg, I've only had one so far @ 55g/sqft - 1.2g/w so not bad. I harvest every 2 weeks so I'll keep compiling and comparing.

 

[Creeperpark]

BobChronic6505, I have found that if I put a LED plant under HPS after the trichomes have developed the last two weeks, or outdoors in morning Sun the last two weeks, the trichomes will turn nicely. I'm talking about 4 hrs morning Sun, and the rest of the day in shade, the weed has a lot more kick too.

Those dense buds will mold if you don't have continual air flow and space around them. Here's a trick, remove a popcorn nugget out of the thickest part of the bud in couple of places on each stem while its in the early pre-bud growing stage. Remove them when they are tiny and small and just starting to flower to keep mold down later in the grow.

 

[Creeperpark]

The slow way if you have clear trichomes, is just put them in a jar after the regular flowering time, and wait 1 to 3 months they will turn.

 

[f-e]

You might find using very little P will reduce side branching. The issue is in the near IR band though. You need it to trigger some sort of mild shade response, to move from branching out to stretching out.


Edit: An incandescent lamp light do it. Just some way of tipping the light balance towards the far-far red, so the plant thinks it's in shade. Where is can no longer afford to bush out, and must stretch in competition with it's neighbours
I used a household lamp myself for a while.

 

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Cheers fe.
I use base nutes so not really in the position to mess with P specifically. 'near infrared band' okay hmm. Oh so I need some red.. damn I wish I just bought the board with the IR diodes. I could just swap it out with one of my my boards in flower that do have the reds.

Edit:
But I'm just leaning towards shelving it and going back to MH, because transitioning from LED veg into LED flower seems to exaggerate or compound the issue further anyways as opposed MH>LED if you know what im saying.

 

[BobChronic6505]

thanks yall i appreciate your responses!