Reasons for no show flowers?

[Barn Owl]

Hello,

I started a short thread yesterday in the soil grow forum, and had more questions and thought this one would be more appropriate.

My plants have been in the 12/12 cycle for just over two and a half weeks. While some have shown gender many have not.

I have a 1000 watt HPS. I am growing organic in soil. There are no light leaks. I have double checked this. Someone told me in the other forum to check PH as high PH may delay flowering and it was 7. I did lower the ph of the water to 6.5.

Other factors to consider are that the temps got down in the 40's for about 4 nights before I caught it and raised it to upper 50's low 60's. I am thinking that may have delayed things.

The plants otherwise look healthy and are doing the 12/12 stretch. The two strains are California Orange (hemcy) and a KC33/Kush hybrid. There are Shiva Skunks that have flowered already. I have grown all these strains in the past with good success. I feed them Age Old Organics and bat guano in flower. Also, many did not have preflowers when I put them in 12/12. They were about 8 inches tall. I do that early to avoid too much height.

Has anyone experienced this delay in flowering? Have cold temps delayed things for you in this department? Trying to decide if I need to do something

Kind of confused and looking for clues.

Thanks for any ideas.

 

[MynameStitch]

Yes, temps will delay and slow down things when they go under 60 F, they can't grow in temps like this; it's like they go into hibernation mode.

Are you giving them a nitrogen fert? If so how much?

Too much nitrogen also contributes to delay of flowering.

Also, if they did not show preflowers before going into flowering; it will take a bit before showing preflowers, some strains can take forever, if they are mostly sativia strains; they can take even longer.

You want to start on the 4th node of where the leaves come from; the sex always gets shown on the main stalk first; and it's always around the 4th node when it does get shown, you can get a microscope with like 20X magnification, make sure it has a light and check where the branch comes out of the main stalk; it wil be in there.

I made a silly looking thing that what the pre flowers look like under the microscope.
THat way I could find out what the sex was before it flowered and not waste time with males.

I am not sure about those strains, there are so many; do you have pics of them?
Which age old organics are you using?
Your temps need to be stable if you want them to stay on track and grow like they should.

Right now temps should not go under 65 and temps should not exceed 85.
People like to use colder temps late in flowering for trying to bring out the colors of cannabis if the strain has the color changing gene.
Right now you don't want to do this this early in flowering; it delays and stunts growth.

 

[Kr@kEn]

You didn't mention the age of the plants. If they are seedlings, most strains will not flower until they reach maturity no matter how quickly you switch to 12/12. Most strains FROM SEED will not show sex until they are 4 weeks old at the earliest.
Rooted CLONES however will start flowering pretty much right away under 12/12.

Other things can affect the onset of flower too, like too much nitrogen or hormones like superthrive or similar. A large contrast in size between veg lighting and then switching to a 1000w can also make the plants take an extra week or so to get going, because of light shock and the plants wanting to get bigger (including the roots and main stalk) under the bigger light before flowering. This is why some veg for at least a week under the big light before switching to 12/12 to get them going under the big light first.
Grow on

 

[MynameStitch]

Where do you get your information from sometimes kraken? Not picking on you dude, but seriousy; where is there proof clones start to flower right away? They don't! I will explain why, when you flip that switch to 12/12 it takes the plant around a week before it starts to release flowering hormones to start it to bloom; does not happen right away, why do you think you are not supossed to switch right over to bloom ferts when you enter flowering; you wait about a week or 2 and then cut off the veg ferts and start using the bloom?

Because they don't flower right away, takes time! No strain flowers right away, if you have a auto flower strain, they too still take time, but they flower on there own.

 

[Barn Owl]

Hey thanks.

They got superthrive in the veg stage but none in flowering.

The fert they are getting is Age Old Bloom 5-10-5. There is nitrogen in that, but not a whole lot. I have used that because the N helps the stretch.

There were no preflowers before the flowering.

They were about 5 weeks old when switched over. They are 7 and a half weeks pushing 8 weeks now.

Sounds to me like it was too cold. I'll monitor the temps better.

Oh, and I can't do the pix now. I have a software problem.

Thanks again.