Environmental changes in week 6 of flower? (Wedding Cake)

lusidghost

Well-Known Member
If you know a strain really well, I imagine you could get it nailed right down to the time it finishes. After a few grows of it in a consistent room anyway.
This is what makes cloning so desirable. After a couple of cycles you understand what they require at each phase, and about how long they will take to finish. Growing multiple strains is tough. Always growing multiple new strains is real tough. I think beginners should pick two strains: one sativa leaning and one indica leaning. Then mother them and grow their clones for a couple of years. Once you've mastered those two strains then you can start experimenting with other genetics.
 

Dr. Who

Well-Known Member
I am running Wedding Cake strain in a 4x4. I've heard that the supposed 8 week strains are more often than not, actually requiring 10 weeks and verified this with various growers who generally agree... reports online indicate that this strain takes from 8 to 11 weeks. So, I think aiming for 10 is reasonable.

...Albeit, 2 of my plants seem to have developed much faster than the other 2 so I might be wise to stagger the harvest as well...

My question is about how to plan for the ripening. Now I've reached week 6 and the advice I have, is to reduce temps/nutrients/light/co2 at this stage and then really reduce it a lot more for week 7-8.

In my case I suppose I will add 1 or 2 weeks to these week counts. But here is the advice I plan to follow:

View attachment 4893935

My question is: how does this all sound? Is it wise to encourage the ripening as such? What are your experiences with that, and any experience with this strain? Or comments on my strategy? Thanks
I wouldn't drop my night temps more then 15 deg F.... Dropping as low as 50? This will slow growth a bit. It takes the plant longer to warm up - especially the root system.... In ANY ebb and flow - HYDRO system or method......NEVER allow the res to get to 70 F..

You'll find out a lot about root rot that way.

CO2 should ALWAYS be shut off the last 2 weeks of the run! It inhibits Ethylene gas production on "fruiting" plants. Budding is the same as "fruiting". So shut that shit off...

Flushing is a MYTH! Proper drying and curing! You can't "flush" nutrient's from plants... You can starve them. Now what happens to fruiting "people" if you starve them? Not so good results eh?

If you have plants that are seeming to turn yellow/finishing up already.

Chances are that the feed mix you use is actually OFF in formulation..... Boosters are generally crap.
I'll guess that the N was lowered to much and the P was increased too much...

BTW. Excess K use - like from boosters - actually inhibits THC production.... REAL care should be taken in the use of K and N.....
 

Dr. Who

Well-Known Member
From what I have read plants put out hormones or chemicals at different stages to basically adjust ph and facilitate different nutrient uptakes.
If that is true, just feed it in ph range and it will take care of itself.

The charts are great. Are you sure your plant is exactly where you think it is on the chart? That is the problem, I had, not being able to read plants well enough to judge close enough for the chart.
Now my plant is in wk 20. chart only went to wk 18... Obviously there is some discrepancy there. I was feeding bloom in veg, because I just read the chart, but the plant was never in line with the chart in the first place.

If you know a strain really well, I imagine you could get it nailed right down to the time it finishes. After a few grows of it in a consistent room anyway.

GREAT IDEA - - BUT, Most feeding chart formulations are actually OFF for cannabis...

A healthy plant should be green to the almost very end. Exceptions are how the strain colors and/or how you run it...
 

Overgrowtho

Well-Known Member
CO2 should ALWAYS be shut off the last 2 weeks of the run! It inhibits Ethylene gas production on "fruiting" plants. Budding is the same as "fruiting". So shut that shit off...
Thanks can you explain more on the negative effect of inhibiting this? Would it hurt terpenes or what? I ask because some people, including me at times, have perpetual flower rooms with co2 high at all times.
 

Dr. Who

Well-Known Member
Thanks can you explain more on the negative effect of inhibiting this? Would it hurt terpenes or what? I ask because some people, including me at times, have perpetual flower rooms with co2 high at all times.

Ethylene gas is produced by the plant to ripen it. It helps initiate, and makes for a smooth and accurate finish.

Gassing a plant during the last 3 or at LEAST last 2 weeks... WILL cause uneven and slow finishing..... More need to do layered harvesting.
Not to mention that the plant is spending more time actually fighting it's self then doing either growing or finishing.
SO YES, your limiting terp and THC production at the bulking phase. Most of all? Your effecting the final yields in a bad way!

Any QUALITY instruction on the use of gassing (no matter what the gas source is.) WILL explain this.

Get out your thick wallet and buy the "Green House Growers Guide"

This is one of the most complete sources for actual indoor growing you can get!

From Gas light routine to the use and/or generation of Co2 and how best to employ it.. This book supplies more then about any other source on Co2 enrichment then even Ed R! Ed may give a cpl of lighting formula's that explain lighting needs but, the GHGG does that too..

This brings me to say that your NOT generating enouth light energy TO utilize 1500ppm. For ANY indoor grower,? that is next to impossible.... It can be done but, the cost to the end user is STUPIDLY high!

The best you can supply? Enough for 1300 ppm! Average home user hits at about 1100 - 1200 ppm.

The EFFECTIVE use of Co2 also requires higher Temps and RH then average for the plants to ACTUALLY USE that extra Co2!
I would run 1200 at low to mid 80's in temps and an RH of at least 70 -74%!

The use of an environmental controller does the job of off and on for - gas, exhaust fans and cooling devices..

GOOD LUCK
 
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Dr. Who

Well-Known Member
Couldnt seem to find it, whose it by?

May bad. Old timers is getting to me (NOT Alzheimer's)....

Greenhouse Operation & Management or known in the industry as Nelson's Greenhouse Guide.

Based on the author's life-long practical experiences both in the industry and in research, this best-selling, state-of-the-art guide to the operation of commercial flower and vegetable greenhouses presents coverage in the order in which decision-making concerns occur. Exceptionally comprehensive, yet accessible, it provides detailed, step-by-step instructions in layman's terms for ALL aspects of the business, from the physical facilities, to the day-to-day operations, to business management and marketing. Specific chapter topics cover greenhouse construction, heating, and cooling; environmental control systems; root substrate; root substrate pasteurization; watering; fertilization; alternative cropping system; carbon dioxide fertilization; light and temperature; chemical growth regulation; insect control; disease control; postproduction quality; marketing; and business management. For individuals entering the greenhouse business.

Look for the 7th edition or newer if they has been another edition after that....

it's like $200 or more.......Look for used otherwise...
 

Dr. Who

Well-Known Member
Thanks one more question is about this RH. Why so high RH with Co2? I've never heard of this before. Seems like the VPD will be out of wack if that is for flower. For Veg, it's fine.
The temp and the RH go hand in hand with the increased Co2.
It allows the extra Co2 to be used effectively by the plant.
 

Overgrowtho

Well-Known Member
The temp and the RH go hand in hand with the increased Co2.
It allows the extra Co2 to be used effectively by the plant.
I've known this about the temperature, and that makes sense to me, but humidity?
I wonder how scientifically, the increased humidity can permit extra co2 to be effective? If there is any scientific backing for that part?
I've always thought that VPD is the governing factor of the humidity setting -- whether using co2 or not.
Are VPD rules altered by extra Co2? How does one draw this conclusion, on the science?
This would be news to me! So, thanks.
 

Roy O'Bannon

Well-Known Member
  • Plants open and close their stomata to regulate moisture loss. If you're using carbon dioxide, you want the plants? stomata to stay dilated to maximize gas exchange.
    • High VPD/Low RH: Plants close their stomata, reducing CO2 uptake.
    • Low VPD/High RH: Plants open their stomata, increasing CO2 uptake.
If your VPD is too low, then your plants aren't going to acquire enough nutrients, slowing growth; if your VPD is too high, you're going close the stomata, rendering your extra carbon dioxide ineffective. There's a sweet spot in the middle.

Link to the whole thing.

Didn't see any actual numbers though.
 

Dr. Who

Well-Known Member
I've known this about the temperature, and that makes sense to me, but humidity?
I wonder how scientifically, the increased humidity can permit extra co2 to be effective? If there is any scientific backing for that part?
I've always thought that VPD is the governing factor of the humidity setting -- whether using co2 or not.
Are VPD rules altered by extra Co2? How does one draw this conclusion, on the science?
This would be news to me! So, thanks.
Look at your bloom VPD chart again.

At 82.4 to 84.2 deg F.
The RH sweet spot is between 70 and 85% RH. Pick the middle ground of between 75 and 80%...

You have to dig around a bit but Ed R talks a lot about Co2 use and environment control.
He's not the only one.

Technically what your doing is recovering the 30-35% growth loss that comes daily from the light saturation point.
This is when the plant actually changes on the cellular peptide level. To actually protect it's self from the intense light of day.
The plant then reverts to it's early state during the night. This is an argument FOR a lights out period in veg AND for growing Auto's.
The continuous argument , that auto's preform/yield better from a 24/0 light schedule. Is not exactly true.
You see you're running a plant at only about 66% efficiency under 24/0 lighting.
HAVING a dark period will bring it back to 100% efficiency for around 4 hrs a day......
THIS will increase plant growth during that time, on a daily basis. See the point?

This is a rule that all C3 plants are effected by.

Research on Google scholar is where you should start looking to learn more about that.
 

Overgrowtho

Well-Known Member
Look at your bloom VPD chart again.

At 82.4 to 84.2 deg F.
The RH sweet spot is between 70 and 85% RH. Pick the middle ground of between 75 and 80%...
I understood these guys were saying to choose on the higher side to make the most benefit from Co2 such as perhaps 77-85% RH?

You see you're running a plant at only about 66% efficiency under 24/0 lighting.
HAVING a dark period will bring it back to 100% efficiency for around 4 hrs a day......
Are you saying then, that it is better to veg in 20/4 instead of 18/6?
 
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