Please help - Switched to LEDs ==> slow growth, no budding!

[Ritualis]

Hi guys,

I’m quite desperate right now so let me skip to the point (at the bottom you’ll find tl;dr)

Setup and performance until now
- Seasoned indoor grower (~ 6 years)
- Setup: 8x4 (240x120 cm) grow tent
- Lighting: 2x 600w HID (Lumatek, Adjust-a-Wings reflectors)
- Method: SCROG
- Strain: Dinafems’ Moby Dick (8 plants)
- Medium: Soil (Plagron) in classic ~10 gal (40L) pots
- Feeding/nutrients: Canna Terra (Vega, Flores, Rhizotonic, Cannazym, PK13/14)
- Grow cycle: From clones to 75% filled screen 18h MH cycle for about 3 weeks and 2 months of 12h flowering.
- Performance: 1 – 1,25 g/W

I wanted to expand operation and due to HID electricity/output ratio turned to LEDs. As preassembled LED systems are very expensive, I did my fair share of research and at the end decided to do it myself.

This is my new setup
- Setup: 8x4 (240x120 cm) and 6,6x4 (200x120 cm) screen (w/o growbox)
- Lighting: 2 x MeanWell HLG-480H-48A each driving 8 x Samsung HinFlux L09 SL-B8V4N90LAWW 3000K Lm301b diode LED strips + 2 x MeanWell HLG-320H-48A each driving 5 x same LED strips. Strips are mounted on ALU profiles (heatsinks) warming up to 58 – 60 C.
- Method: SCROG
- Strain: Dinafems’ Moby Dick (8 + 4 plants). 4 plants are under additional 6,6x4 (200x120 cm) screen.
- Medium: Soil (Plagron) in ~13,2 gal (50L) AIR pots.
- Feeding/nutrients: Canna Terra (Vega, Flores, Rhizotonic, Cannazym, PK13/14)
- Grow cycle: From clones to 75% filled screen 18h MH cycle for about 1,5 month and almost 3 weeks into flowering I got first signs of buds.
- Performance: /

So, main three changes are the lighting, removal of grow tent and pots. There were previous attempts to expend operation by setup additional screen and putting lights on light movers, but that setup just didn’t give enough light and performance was poor (even less than in tent, about 0,8 g/W). Everything else was the same.

What is the problem now? Veg took twice the time it took under HIDs, but OK, these LEDs are 3000K so I was expecting slower growth. However, the main problem is that even 3 weeks into flowering I don’t see any real budding. With HIDs it usually took just a couple of days for first pistils to appear, now 3 weeks into flowering only few can be seen... Otherwise, plants are looking very healthy, no visible problems etc.

I attached few pics for better understanding.

Can someone please explain what am I missing, doing wrong, should be doing differently and most importantly should I keep my optimism or expect failure?

tl;rd: Switched from HID to LEDs, rate of growth and flowering are very slow and in general just underperforming.

 

[mnmobbin]

What are your temps? I experienced just the opposite when I went to led the growth exploded. The one thing I did have to do was setup a heater in my lung room to raise ambient air temps as the led is running much cooler. My room sits around 79f now and the plants are loving life.

3000k shouldn’t be giving you slower growth, in fact it should help the plants stretch a little bit more than say 4000k which gives me nice tight node spacing.

 

[boilingoil]

How do you have your sq.ft. set-up? Watts per sq.ft. your trying to achieve ?

 

[Ryante55]

Hi guys,

I’m quite desperate right now so let me skip to the point (at the bottom you’ll find tl;dr)

Setup and performance until now
- Seasoned indoor grower (~ 6 years)
- Setup: 8x4 (240x120 cm) grow tent
- Lighting: 2x 600w HID (Lumatek, Adjust-a-Wings reflectors)
- Method: SCROG
- Strain: Dinafems’ Moby Dick (8 plants)
- Medium: Soil (Plagron) in classic ~10 gal (40L) pots
- Feeding/nutrients: Canna Terra (Vega, Flores, Rhizotonic, Cannazym, PK13/14)
- Grow cycle: From clones to 75% filled screen 18h MH cycle for about 3 weeks and 2 months of 12h flowering.
- Performance: 1 – 1,25 g/W

I wanted to expand operation and due to HID electricity/output ratio turned to LEDs. As preassembled LED systems are very expensive, I did my fair share of research and at the end decided to do it myself.

This is my new setup
- Setup: 8x4 (240x120 cm) and 6,6x4 (200x120 cm) screen (w/o growbox)
- Lighting: 2 x MeanWell HLG-480H-48A each driving 8 x Samsung HinFlux L09 SL-B8V4N90LAWW 3000K Lm301b diode LED strips + 2 x MeanWell HLG-320H-48A each driving 5 x same LED strips. Strips are mounted on ALU profiles (heatsinks) warming up to 58 – 60 C.
- Method: SCROG
- Strain: Dinafems’ Moby Dick (8 + 4 plants). 4 plants are under additional 6,6x4 (200x120 cm) screen.
- Medium: Soil (Plagron) in ~13,2 gal (50L) AIR pots.
- Feeding/nutrients: Canna Terra (Vega, Flores, Rhizotonic, Cannazym, PK13/14)
- Grow cycle: From clones to 75% filled screen 18h MH cycle for about 1,5 month and almost 3 weeks into flowering I got first signs of buds.
- Performance: /

So, main three changes are the lighting, removal of grow tent and pots. There were previous attempts to expend operation by setup additional screen and putting lights on light movers, but that setup just didn’t give enough light and performance was poor (even less than in tent, about 0,8 g/W). Everything else was the same.

What is the problem now? Veg took twice the time it took under HIDs, but OK, these LEDs are 3000K so I was expecting slower growth. However, the main problem is that even 3 weeks into flowering I don’t see any real budding. With HIDs it usually took just a couple of days for first pistils to appear, now 3 weeks into flowering only few can be seen... Otherwise, plants are looking very healthy, no visible problems etc.

I attached few pics for better understanding.

Can someone please explain what am I missing, doing wrong, should be doing differently and most importantly should I keep my optimism or expect failure?

tl;rd: Switched from HID to LEDs, rate of growth and flowering are very slow and in general just underperforming.

The lights look really far away from the plants if the temps are also low that could cause the problem. At the end of the day it's grower error

 

[Ritualis]

What are your temps? I experienced just the opposite when I went to led the growth exploded. The one think I did have to do was setup a heater in my lung room to raise ambient air temps as the led is running much cooler. My room sits around 79f now and the plants are loving life.

3000k shouldn’t be giving you slower growth, in fact it should help the plants stretch a little bit more than say 4000k which gives me nice tight node spacing.

I also do expirience lower temps, right now I have 15C at lights off and 21 at lights on.

 

[Ritualis]

The lights look really far away from the plants if the temps are also low that could cause the problem. At the end of the day it's grower error

I would be very happy if it is my error I'll try lowering the lights, but I have noticed a little bit of bleaching when they were closer.

 

[ANC]

You have to keep in mind how the original stock was selected, i.e. was it grown indoor or outdoors, was it grown under full spectrum LED or HID or blurple, etc...
When we run some strains outside of what they were selected under they don't perform. Some strains will put down for 600W, others will laugh until they see at least 1000W

My LED strips have to touch the plants to harm them and then it literally only makes little white spots in the pattern of the LEDs, where they touched,

 

[mnmobbin]

Bump those temps up good sir 15-21c is pretty cold for your ladies. I’m thinking that’s the major factor as your hid setup was throwing a ton of heat into the room and the strips are not.

 

[boilingoil]

70F is too cool for optimal growth.

 

[Ryante55]

I would be very happy if it is my error I'll try lowering the lights, but I have noticed a little bit of bleaching when they were closer.

Your temps are pretty low at 21c. How far are the lights now? Every build is different but I would think you could get like 12in away or closer with the strips without a problem. If you have the lights like 2 feet away you won't see very fast growth

 

[ttystikk]

I also do expirience lower temps, right now I have 15C at lights off and 21 at lights on.

Low temps are a big part of your problem. HID throws a ton of infrared- that's why they're less efficient- so to compensate for this, growers have run lower temperatures.

LED lights don't emit nearly as much infrared so ambient temperatures have to be substantially higher; 30C/85F is ideal. You'll also want to watch your humidity, 70% RH at 30C is a good mark to aim for.

You're getting bleaching because the girls aren't transpiring enough at low temps to feed the leaves. Warmer temps will solve that, as will a stronger nutrient mix.

It takes time to reset your thinking to take advantage of LED lights but it's well worth the effort!

 

[Ritualis]

What are your temps? I experienced just the opposite when I went to led the growth exploded. The one thing I did have to do was setup a heater in my lung room to raise ambient air temps as the led is running much cooler. My room sits around 79f now and the plants are loving life.

3000k shouldn’t be giving you slower growth, in fact it should help the plants stretch a little bit more than say 4000k which gives me nice tight node spacing.

Hi,

OP here. Don't know if anyone will see this, but it was temperature all along! Fixed that and had a pretty good round. The following (summer) round now was exceptional to say the least! Thanks again, wish you all good growths.

 

[mnmobbin]

Hi,

OP here. Don't know if anyone will see this, but it was temperature all along! Fixed that and had a pretty good round. The following (summer) round now was exceptional to say the least! Thanks again, wish you all good growths.

Glad to hear you got it figured out!