Question...When to Water...@ lights ON or lights OFF

[Insight]

I've searched this question on google....came up with many discussions on other forums with mixed answers....but saw nothing from GWE..so I'll ask here.

I am trying to plan for the flowering stage in a few weeks and will have to switch to 12/12 and trying to figure out what my start and end times should be. It takes about 1.5 hours to make up the nutes, water the 3 girls, vacuum up the waste water, etc.

I thought I'd arrange the schedule so I could feed when I returned from work...so a 7:45 am to 7:45 pm schedule would probably work well during the week.
I leave the house around 8:45 am and return around 6 PM.

If I have to water at lights ON, then I would re-arrange the schedule to something like 6:15a - 6:15p, but really do not want wake up that much earlier, and would leave me no time to deal with them when I get home around 6 PM.

My concern was watering just before the lights go off. What about the increase humidity? Possible mold production. Even now, about 4+ weeks vegetative stage, the humidity goes over 50%, with lights off, exhaust fan off. I will, when flowering, leave the exhaust fan on 24 hours/day. Don't know what the humidity will be, especially as we get further into the Spring and the humidity naturally rises. I have dehumidifier running in the basement that keeps it around 55-60% rh.

I can, and if needed will, tap into the HVAC and put a vent line into the tent..now the vent goes into the room that the tent is in...this should help with overnight temp and humidity.

So, is there a consensus here on GWE as to when to water...lights On or lights OFF?

Your thoughts would be appreciated.
TIA

[furrysparkle]

I'm also interested in this answer, however it'll be for DWC

[Newf]

How about lights on at 8pm and off 8am or 7pm to 7am. That would keep the heat down during the day and you might not need the AC. You can water/feed before you go to bed. By having lights out for 12 of the the hours you are not at work you are really limiting the hours you have available to you with the lights on. If you really want to have lights on during the day so you can work on them on your days off during the day you could do a noon to midnight lights on. That way if you water when you come home from work you still have a few hours of lights on keep humidity down, but you will have lights on for the hottest part of the day.

[Insight]

Newf all good ideas. I thought of the schedule you suggested. I may go with that.

My original schedule was done with keeping nighttime (lights off) temps lower than lights on temps. My night time temperature in the basement is lower than daytime temperatures.

I also tend to lower the AC temperature when I'm sleeping.

I'll keep your suggestions in mind. Thanks.

[9fingerleafs]

I know it's best to water when the light are on. Flood and drain and other timed watering techniques are programmed to work during the light cycle. Leaving the soil super wet at night reduces the amount of oxygen the roots "breath" and the plant kinda has to wait. That being said. I don't think what time you water is going to have more impact on the final product than having enough time to take care of them and having a schedule that works for you. So I would stick with the watering at night if it gives you more time to do everything right. It makes less of a difference if you don't have to water everyday

[Insight]

Thanks.

[NA420]

I wake up meditate, nourish. After i get myself right i get my plants right! A clear mind helps the plants and myself. So 12a-12p my lights are off by high noon and i have the rest of the day to go out and inhale negative and exhale positive! My plants never feel my prime time stress lol. Peace!

[oldjarhead100]

I always thought the if lights go on at 7 every day they should stay with the same on time the whole grow. I would research if you can change on time before you change it .The plants will certainly survive but it may extend your grow time by stressing them out.

[PaganRich]

I try to water a couple of hours before lights out however that is mainly for my suitability yet I think they also need that off time just to drink peacefully when the lights are off...bit like going to the pub in the evening...also, any spillage on leaves has less burn time...good question....