Week 7 check-in for 1st-time autoflower grow

Hi All,
I am in week 7 (seeds germinated 47 days ago and sprouted 44 days ago) for growing 6 auto flowers- 2 Northern Lights, 2 Amnesia Haze and 2 Blueberry- all 6 seeds sprouted! They seem to be doing OK but I have pictures attached for better community judgement. My questions are mainly due to conflicting advice and opinions on some important topics. I’ll do the questions first and then provide my specifics as to what I’m using:

  1. I have been doing 20/4 since seedlings. I keep hearing that plants need art least 6 hours of darkness to properly grow. OTOH, there’s the opinion that you can never have autoflowers get too much loght (short of the fixture burning them). Who is correct? And, related, if I can do full-spectrum with my fixture while maintaining good airflow/temp/humidity, should I, or should I just use the red cycle?

  2. How much water, really? So far, I’ve been watering every 2 days. Using FFOF and grew from the seedling straight into my final growing medium of 11 liter pots, but did create a depression the size of a 5’ planter to use Black Gold seedling soil so that the seedlings wouldn’t grow straight into the too "hot " for seedlings FFOF. I have been doing so far so good with watering gradually; they’re now up to 1 liter of water or so each every two days. Other advice is that I should be watering to 10% runoff every day. Who is correct?

  3. Grooming- I haven’t done any removing (except for two damaged leaves) to open up the plant space to get more room to the bud sites. I’m still at late veg/early flower, depending on the plants. The Amnesia Haze ones are barely beginning to flower but I’d expect that’s normal given they’re sativa and take a while longer to develop. As this was my first autoflower grow I only did LST on one plant, just to see the results. It did seem to create more bud sites. Should I be taking any leaves now? I understand overgrooming is not recommended, but other growers seem to swear by the results, so I’m at a loss of what I should do (if anything) and when.

  4. I’m doing 6 plants in a 24"X 48" X 84" Gorilla tent with decent ventilation and lights. Is that too many plants for the tent size? Would I really benefit from removing a couple and letting ambient/flourescent light take care of those, hope for the best, and get a better yield with the remainders?
    Thanks all for the help.
    Specifics:
    -24" X 48" X 84" Gorilla Grow tent
    -AgroLED Dio Watt 720 low pro with veg and bloom switches; consumes 450 watts to produce 720W from 240 led lights, full spectrum.
    -FFOF soil with Black Gold for seedlings, water filtered and Ph’ed to 6.2-6.5 (though I am getting some lower runoff, so may need to adjust)
    -6" 65 -watt 3-speed exhaust fan with carbon filter

Thanks so much and please see attached photos of girls and setup:Blueberry 2 (lost picture of #1), and exhaust fan, light set up, and interior of tent from side and above.

2 Likes

First of all welcome. Ladies are looking good. As far as I’m concerned everything needs rest including plants. So I do the 18/6, no reason other than following convention and like I said everything needs down time. Watering for me means a little runoff purely to measure my PPMs and PH, anymore than a little I feel is a waste. As for grooming, I remove for circulation and light penetration then towards the end I defoliate to let them concentrate on bud sites, again purely practical for me. As for plants I have 8 in an 8x4x6 but feel it’s going to get crowded. Lighting is @dbrn32 department, I’ve tagged him so he will be along shortly. @Hellraiser does a lot of defoliating, I’ve tagged him as well as he knows a lot more than I do about the reasons why. The answers I’ve given you are based on what works for me and what I’ve learned as I go along with zero science behind it. Hope it helps, lot of good growers here so you should get the answers you’re looking for.

1 Like

Welcome to the community. I am pointing out one problem area.

I’m no expert on problems so I will tag one that does. @Myfriendis410

3 Likes

@MrPeat is pointing out what looks like a calmag deficiency, you should add 5ml/gal of CalMag to your water, assume you’re using RO or distilled?

My thoughts on your questions:

  1. I feel anything over 18 hours is unnecessary if you are using strong lighting. Use full spec - all switches on, the more light during flowering the better as long as you can keep the temps in check.

  2. You should water when the plants are dry and need water, whether thats every day or every 5 days, I always water to runoff to help wash out salts from the fertilizers and to ensure I have moistened all the dirt in the pot, don’t want dry spots. Water fully, then let dry up, wet/dry cycles is what you want.

  3. Not an auto guy but I remove leaves as needed to get light to bud sites/branch tops. Usually week 3 of flowering is best considered the time for major defoliation, some people take every large fan leaf at that time. I’m not so extreme.

4.Seems like too many plants, like when I used to do 9 plants in a 3x3, was very crowded but I made it work but I prefer doing 4 in a 3x3 now, you will want to defoliate a lot when crowded like that to get light below the top canopy.

4 Likes

Thanks for jumping in @Hellraiser. :+1::+1::+1:

2 Likes

Thanks for all the feedback so far! I thought the one mottled leaf looked suspicious as well, so good to hear I can fix it with some cal mag in the water. Good advice from all.

1 Like

Kinda looks like condensation burns.

2 Likes

Cannabis is a C3 plant, it doesn’t need any amount of dark time to grow properly. However, autoflower is no different than photoperiod in terms of how much light it can process. There is indeed a point in which it will reach a maximum of amount of energy produced. This is dependent on amount of water and co2 available usually. Reasrch Daily Light Integral for in depth explanation. Use the entire light.

The exact amount of water isn’t as crucial as making sure they get enough water, and are allowed to dry out so roots can get some oxygen. I believe most people suggest watering to a small amount of runoff so they are sure plants get enough water and to potentially test as mentioned above. In a different media there would be other justifications to water to runoff, but is not necessarily needed in soil so long as other conditions are satisfied.

Airflow is important to maintain healthy plant. Other trimming of plant would be done to make sure parts of the plant you’re intending to keep are getting adequate light. You shouldn’t ever take more than you need to, how much can vary by plant, or even by specific method. A scrog will usually get a good stopping around flip, and then some light maintenance all the way through flowering. The way you’re growing you could probably clean up a little bit after transition and then again maybe 2-3 weeks later. Blurple light may not even create the leaf density to justify doing it at all. This is something you will have to get feel for on your own over the course of a few grows. Definitely err on the side of taking less though.

How does it consume 450 watts to produce 720? It’s a light not a generator. Important to identify that light isn’t measured in watts. There’s a big range of efficacy in different lights. One 450 watt fixture can produce a lot of light, while another may not products much at all.

If all the plants fit in your tent I I don’t see any reason to remove any of them.

1 Like

Thanks so much for your detailed responses! Yes, the power consumption of my lights doesn’t really indicate much, but I’ve been trying to figure out what they’re putting out in lumens. I think I can get away with keeping what I have in the tent as well, especially if I do some careful and targeted grooming to increase airflow.

1 Like

Looks like you’re getting some properly weighted responses there @room2grow. I’m very much an amateur, these guys are the closest thing you will get to professionals. Hope their answers help in guiding you to where you need to be :sunglasses:

2 Likes

Welcome aboard! Plants look really healthy!

Thanks, so far they seem right on target. I have some purple stems happening on a few, also a sign of cal mag deficiency, probably due to the household water filtration we have that does remove lots of chlorine, but also other stuff I need!

1 Like

Thanks much! I seriously appreciate all the responses that’ll keep them that way.

1 Like