Plants are coming up on 8 weeks old -when do I switch lights to 12/12

First time grower here. Have three plants we were told were feminized (got them from my sons friend) that sprouted around March 31st. I just topped them last weekend. So far they have been growing robustly in Happy Frog soil in 7 gallon bags in a 3x3 tent in the basement. Wondering if it is time to put them in flowering mode ?

I typically flip when the plants are half the size I want them to be in the end.

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Half the height?

The rule I use is if the plants are covering 50% of the grow space you can switch to flower

Correct. If I’m scrogging the plants then I wait until 50-60% of the net is filled then flip and fill out the rest of the net during the flower stretch.

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I am going to post a picture of my setup later. I fear that i am already covering all the grow space : O

Transplanted 4/23. Already about there! LOL

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It’s fun when they actually grow like weeds

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This is what they look like as of last night . It is a 3x3x6 tent

@MrInteresting you can flip them yesterday if you ready ? Your trellis is not in there yet and it’s full in there , it you going to trellis , place right on top of them and which ever stick through good , and weave the rest in where you want them to stretch and enjoy the next 8 weeks of fun !

A couple of things. What do you have for lights? Are they set at the right height. The reason I ask is you have large internodes which can happen if the light is set too height. Or, it can be the strain. Sativa’s will not be as compact as indicas.
Are you going to use a net? One would help manage the height.
This is always worth keeping in mind.


where do i get the trellis?

This is my first ever grow so I am winging it so far. The light is an HLG rSpec 100 and I had it at 24 inches per the instructions from HLG but as the plants grew that distance got smaller. Right now they are probably only about 15 inches from it. I got a second light that arrived yesterday and need to rework the exhaust and filter setup to get both lights in the tent. I wish I had bought a larger tent at this point but it is what it is. I can grow tomatoes and peppers but this is a whole new ball game so to speak. So any advice would be greatly appreciated. I dont want to lose these plants.

I use a 3x3 tent too. Although I topped and did a little LST on my first grow (white widow auto) they got a little unruly. I try to always grow 4 plants at a time. So the main thing I did was learn and apply LST to manage the size and shape of the plant. My current grow of purple haze is testing me. Two are out growing the other two and stretching more.
Inadequate amount of light will cause them to really stretch. Good you have another light.
Did you change to 12 hour cycle yet?
Post some current pictures, full plant side shots, so I can see what they look like. Also a group shot in the tent. How tight are they now.
What is the tent’s height.

thanks I have not switched the light cycle yet. I hope to get the second light in there tomorrow. The tent is 6 ft tall. They are pretty tight in there right now. I just topped them a week ago for the first time but have done no other trimming . I will post those pics tomorrow.

Here are some pics of where I am at right now with the plants. What am I doing wrong? What am I doing right ?

Many thanks in advance!

You topped them once. I think you would do well to do it again and remove the scrubs on the bottom

Now that you have another light the internodes should not be as large.
I could not tell exactly where the growth tips are. I wanted to show the branches being cut above the second growth tip. This will leave you with four at the very top.
On the bottom I would remove the two sets of branches at the very bottom. They more than likely will never come within a decent distance from the light and not amount to much. I think it is better the resources they would otherwise consume be redirected to the rest of the plant.

Do the same thing to the other two. The goal is to shorten them up and have as even a top across the plants as can. Give them 4 days to recover and then flip them to 12/12. Set your lights at flower height (18-20"?) and as they stretch raise the light to keep that distance. My hope is with topping the two mains and pruning out the bottom, they will fill in more.
How does that all sound?

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Thanks. Sounds like a plan. Could you explain what you mean by the “second growth tip”?
The bottom cleanup sounds pretty straightforward: just snip the two lowest shoots?
I can send better pics if needed

Growth tips…
A growth tip usually emerges where the leaf stem intersects the branch it is growing out of. These growth tips eventually produce calyxes and colas. The intersection of a leaf stem and a branch is a Node.
Think about when you topped them. Each plant had one primary growth tip. And below it many / several secondary growth tips. The act of topping obviously stops the original primary growth tip (apical stem) and transforms the two secondary growth tips below where it was topped to now become two primary growth tips rather than just one.
Another thing about growth tips. When a plant is young, growth tips and leaf stems grow is sets of two that are opposite of each other. Makes them easier to id and count. The V formed where it is topped is a good example. When a plant gets older, the growth tip & leaf pattern changes to an alternate pattern.
I cropped a section of one of your pictures and tried to identify what I see to be a growth tip

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Ok thanks. A lot of info to process. The pic was very helpful. I still don’t quite understand how the next topping should proceed properly.