12/12 from seed

Hey guys. I'm pretty new to growing and am working on my first grow right now. Been veging for about 3-4 weeks and have just set them to 12/12.

But, my question is about going 12/12 from seed. I'm wondering how this is done exactly? Obviously yeild will be less, but grow time is also alot less. Should you be using 2700k from start? Or use 6500k then switch as soon as flowers show? Also, how about nutrition. You start high Phosphorous already, or start with high Nitrogen, change nutrition when the flowers show. Any other info would be great. Cmon, speed growers. Fill me in.... sprucezues, i know you got this ish now, fill me in.

My first grow I did 12/12 from seed. I used a four foot four tube t-5. The seeds showed sex in three weeks. Before they showed sex I was using two 6500k and two 4100k. When they showed sex I switched the two 6500 for two 3000k tubes and kept the 4100's.

I'm wondering how this is done exactly?

Simply use a flowering light/dark period schedule ( 12/12 ) from the moment the seed pops leaves.




Obviously yeild will be less, but grow time is also alot less.

Yeild will probably be less than a standard veg for a month+ then flower however, growtime isn't always less. It will still take a around a month to show sex then it will be another 8 or so weeks till harvest. These factors depend on strain and what your methods are for growing.


Should you be using 2700k from start?

I would mix them if using cfls.



Also, how about nutrition. You start high Phosphorous already, or start with high Nitrogen, change nutrition when the flowers show.

You should start with veg nutes because the plant still needs nitrogen for growth.


Any other info would be great. Cmon, speed growers. Fill me in.... sprucezues, i know you got this ish now, fill me in

Personally I am not doing 12/12 from seed. I see much more potential with mothers and clones flowering the clones from root.

Heads Up said:

My first grow I did 12/12 from seed. I used a four foot four tube t-5. The seeds showed sex in three weeks. Before they showed sex I was using two 6500k and two 4100k. When they showed sex I switched the two 6500 for two 3000k tubes and kept the 4100's.

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Interesting... Have you found any differences using spectrums in between. I always thought it was just 6500 for veg, and 2700 for flower. I use 3x40watts(top) of 6500 for veg, and 3x40watt(top) + 4x23watt(sides) 2700 for flower. Should I be adding or changing some of the bulbs for veg/flower?

macandhans said:

I'm wondering how this is done exactly?

Simply use a flowering light/dark period schedule ( 12/12 ) from the moment the seed pops leaves.




Obviously yeild will be less, but grow time is also alot less.

Yeild will probably be less than a standard veg for a month+ then flower however, growtime isn't always less. It will still take a around a month to show sex then it will be another 8 or so weeks till harvest. These factors depend on strain and what your methods are for growing.


Should you be using 2700k from start?

I would mix them if using cfls.



Also, how about nutrition. You start high Phosphorous already, or start with high Nitrogen, change nutrition when the flowers show.

You should start with veg nutes because the plant still needs nitrogen for growth.


Any other info would be great. Cmon, speed growers. Fill me in.... sprucezues, i know you got this ish now, fill me in

Personally I am not doing 12/12 from seed. I see much more potential with mothers and clones flowering the clones from root.

Click to expand...

Ic. So there is there any real advantage doing 12/12 from seed? Well, since it takes a month for it to flower. I thought It flowers as it vegetates.

I've never tried spectrums inbtween 6500 and 2700 don't know how well they'd work tbh.

It makes sense that you would start with probably more or all 6500k while they are young with the bulbs very close to reduce as much stretch as possible. When they start to flower add more 2700k and use those primarily through flowering with a few 6500k. Be aware though that 3 foot 12/12 from seed plants are possible, probably bigger, lol.

supernor said:

Ic. So there is there any real advantage doing 12/12 from seed? Well, since it takes a month for it to flower. I thought It flowers as it vegetates.

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If you only have room for one growbox and dont' want to wait months between harvests then 12/12 from seed has an advantage. You can have a perpetual harvest by filling your box, weeding out the males and replacing them with fresh seeds.

supernor said:

Interesting... Have you found any differences using spectrums in between. I always thought it was just 6500 for veg, and 2700 for flower. I use 3x40watts(top) of 6500 for veg, and 3x40watt(top) + 4x23watt(sides) 2700 for flower. Should I be adding or changing some of the bulbs for veg/flower?

Click to expand...

I bought an industrial lighting fixture, it's called a high bay light. It came with four 4100 tubes. I paid a hundred thirty with shipping. I didn't have the money for eight tubes so I bought two 6500 and two 3000. To the best of my knowledge you can't get a 2700 for t-5's You could use 4100 for your entire grow, my buddy did and they turned out good.

macandhans said:

If you only have room for one growbox and dont' want to wait months between harvests then 12/12 from seed has an advantage. You can have a perpetual harvest by filling your box, weeding out the males and replacing them with fresh seeds.

Click to expand...

Now that is an idea!

I ended up doing this without even realizing it. I was playing with bag seed in one of my outdoor planter boxes. It was already toward the end of september, but I figured what the hell, it's still free weed come harvest. I threw the beans in, didn't give it much thought, and now I got a few small plants that are due to be chopped any day now. And I because I expected a small yield, I didn't do much as far as feeding them. Just worm castings and water.

At the same time I was doing an indoor grow. I was letting one plant get really big, thinking one plant would be easier to maintain then a small crop. I completely had it backwards. With the large plant I had to deal with nutrient buildup and lighting.

Looking back, I see both methods have their places, but for small personal grows, 12/12 from seed is pretty smart & stupid simple. Even more so if your in SoCal where you can grow year round