When to flip to 12/12 and 36hr dark period

I am looking for some advice as to when i should flip the ladies below to 12/12...... also, do i give them the 36hr dark period at the start of flowering, i have done it but do not have enough comparisons to tell if it makes noticable difference, though i will say it SEEMS to work, any thoughts greatly appreciated. (centre and centre rear pot not included lol) one's a midget and the other is a dwarf, no offence to people with that disposition.

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how tall are they? i'd let them go a bit longer before starting flower but depends on what you want to yield/how much space you have ect. a 36 hour dark period may help to induce flowering slightly faster, but i feel the difference would be so negligible at the other end it'd be healthier for the plants to just switch it up as gently as you can, since plants don't naturally go into dark for a day and a half
happy smokings

I'd recommend 2'-3' at least before you flower them for best results.. Most people recommend 7 sets of true leaves minimum before you flower...

When you do decide to flower however, just switch it to 12/12 for best results.

MEWINGWOLG said:

how tall are they? i'd let them go a bit longer before starting flower but depends on what you want to yield/how much space you have ect. a 36 hour dark period may help to induce flowering slightly faster, but i feel the difference would be so negligible at the other end it'd be healthier for the plants to just switch it up as gently as you can, since plants don't naturally go into dark for a day and a half
happy smokings

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hi m8, thanks for reply, they are about 16in tall now and i was going to give them a few days to a week (monday or a week monday, today being thursday).
so a straight switch to 12/12 sunday night is all thats required??
i've grown them in 11.5L pots, flowered from 14in and had 46g on one and 63g on another. the strain is bella donna from Paradise Seeds btw. she has a nice compact bud structure with very close internodes.

This time they're in 18L pots... more stretch???

yeah for sure i did some ladies to about a foot tall evenly before flower. the sativas got to be about 4 foot from there and the indicas just got over 2 foot. harvesting a whino on thursday! yeah i'd say make sure the lights go off earlier the night you plan to switch, to ensure they get 12 hours dark time, this is the most important thing, as long as the plant has MORE than 10 hours uninterrupted darkness it'll start flowering and no from my understanding veg in large pots creates less stretching but allows taller plants, one reason for stretch is not enough medium so using bigger pots can never really hurt unless you have a problem with vertical height! give your plants plenty of medium to keep internodes nice and compact

In my experiences, stretching is due to low light intensity and not the size of the pot.

mc130p said:

In my experiences, stretching is due to low light intensity and not the size of the pot.

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i have a 600w hps at a constant 16in from the canopy, about right atm? plan on dropping it to 14 for flowering?