Questions about switching from 24/0 to 18/6 and RH/Temp

[Laserawesome88]

Hi Everyone- first time grower here. I have two plants both on day 29 and they are doing well so far. Any advice for the issues below would be very very appreciated!

My lighting schedule has been 24/0 since sprout under a Mars TS600 with no problems maintaining temp at 25c and and humidity from 70% early on to 55ish% now with very little need for my exhaust fan. Yesterday I changed the lighting in this tent to a TS1000.

The past 24 hours, the outside temps and humidity have gone up considerably and now it is hard for me to keep my plants at the temps and humidity they were used to. The temps in the tent have gone up to 27c and RH is around 60-62% with my exhaust (t4) at full blast with a large dehumidifier outside the tent and fans blowing the exhaust air away from the tent. This morning when I checked my plants they didn’t look very happy (a little droopier than usual).

This has me worrying about what the rest of the summer has in store as it gets hotter outside. I will be into flower by then and if I can’t get my humidity under 60% now, then it definitely won’t be as low as it needs to be in flower (45%).

The first step I took was to initiate a return with ac infinity so I can upgrade from the t4 to the t6. I only have a 2x2x4 tent, and I thought the t4 would be enough, but now I know I definitely need more exhaust power. I am using passive intake and the basement room the tent is in does not have air conditioning so that makes things tricky.

I am also thinking about switching from the 24/0 light cycle to 18/6 during the day. After 29 days of 24/0 will giving the plants 6 hours of darkness cause any problems? This would help me deal with the higher temps during the day, but I don’t want to shock my plants.

Also- Does anyone have any advice to help keep my RH lower?

Thanks!!!

Here are my Mephisto girls: DBCx3BOG on left, CDLC on right at 29 days.

 

[Death The Cultivator]

Hi Everyone- first time grower here. I have two plants both on day 29 and they are doing well so far. Any advice for the issues below would be very very appreciated!

My lighting schedule has been 24/0 since sprout under a Mars TS600 with no problems maintaining temp at 25c and and humidity from 70% early on to 55ish% now with very little need for my exhaust fan. Yesterday I changed the lighting in this tent to a TS1000.

The past 24 hours, the outside temps and humidity have gone up considerably and now it is hard for me to keep my plants at the temps and humidity they were used to. The temps in the tent have gone up to 27c and RH is around 60-62% with my exhaust (t4) at full blast with a large dehumidifier outside the tent and fans blowing the exhaust air away from the tent. This morning when I checked my plants they didn’t look very happy (a little droopier than usual).

This has me worrying about what the rest of the summer has in store as it gets hotter outside. I will be into flower by then and if I can’t get my humidity under 60% now, then it definitely won’t be as low as it needs to be in flower (45%).

The first step I took was to initiate a return with ac infinity so I can upgrade from the t4 to the t6. I only have a 2x2x4 tent, and I thought the t4 would be enough, but now I know I definitely need more exhaust power. I am using passive intake and the basement room the tent is in does not have air conditioning so that makes things tricky.

I am also thinking about switching from the 24/0 light cycle to 18/6 during the day. After 29 days of 24/0 will giving the plants 6 hours of darkness cause any problems? This would help me deal with the higher temps during the day, but I don’t want to shock my plants.

Also- Does anyone have any advice to help keep my RH lower?

Thanks!!!

Here are my Mephisto girls: DBCx3BOG on left, CDLC on right at 29 days.
View attachment 1196431

You are using air pots with frequent air exchanges at max 200cfm. Do they need to be watered?

45% humidity in flower is an arbitrary number and means nothing without factoring your ambient temperature.

Have a look at this link and see if you can't figure out an optimal range for the equipment you have on hand.

Wouldn't be an issue switching to an 18/6 schedule.

 

[automan2]

I drop all my plants from 24/0 to 12/12 at 2-3 weeks old...no issues.
On humidity....I too have high humidity days....and all I do is keep air movement in the tent....

 

[Laserawesome88]

Thank you guys! I will check out the info.

 

[tip]

I think the plants are getting more light than they need with your new lamp and are just a little fatigued. Calculate the DLI they are getting if you have a PAR meter(best) or use the chart provided by the manufacturer if you trust them. If you're way over 40, recalculate with 18 hours to get closer to 40. Make sure your new lamp is not too low first but I think switching to 18/6 will benefit them. You will have to pay more attention to humidity with the lights off and will likely be running the dehumidifier during that interval.

 

[Laserawesome88]

Thank you! I looked at this and with a 19/5 schedule they will get ~41 Mol/sq m a day. Starting this schedule today. I had never heard of DLI! Much appreciated.

 

[Simplicio]

I use humidifiers to keep my autos at about 65% humidity seed to harvest in hydro, and have never had bud rot.

 

[Mañ'O'Green]

Going to 18/6 is an excellent strategy for heat control. Not only that but giving your plants a night time will improve the quality of the end product. At least it did for me when I was experimenting with different day lengths. 18/6 was the winner for autos and other than for germination this is my schedule. I grow Photoperiod plants in the summer so 12/12 gives me even more time with lights out. It was 107°F here the other day much too soon.