whats the earliest i can force flower my seedling to determin there se

[vaughn]

i have a new set off seedlings on there way and was wndering at what age can i put the lights down to 12/12 so they show if there male of female. they have just started growing there second set of leaves also will this stunt there growth much when i put the lights back to 18/6.

[Chronmasta]

High mate

If it were me i would veg for at least 2 months and then take clones for determining sex

 

All the best,

 

 

 

Chron

[OrbitTime]

i have a new set off seedlings on there way and was wndering at what age can i put the lights down to 12/12 so they show if there male of female. they have just started growing there second set of leaves also will this stunt there growth much when i put the lights back to 18/6.

 

 

You can run seedlings from the start on a regime of 12/12 and they will express their sex within 4 weeks while standing 6 inches tall. Remember, if you force flower seedlings for gender you will have to cycle the plant through *heteroblastic development in a vegetative regime before you can re-flower it. Failing this step will give a very poor flowering. The time lost is probably not worth it.

 

Further, while this force flowering method can determine their gender (and can be handy in testing batches of feminised seeds) it is by no means an acceptable method for determining a keeper. To determine a keeper requires alternate phyllotaxy and pre-flowers which come with maturity, usually at the 6th to 8th week of 18/6. It is at this stage you then flower at 12/12, thereby achieving an optimum expression of the phenotypes for you to decide which is the best batch of females; based on trichome abundance, weighty buds and which smokes up to your satisfaction? There may be other factors such as mould resistance or a desire for short and stocky plants because your grow has a low ceiling. None of this is possible to determine by a force flowering of seedlings.

 

If you take cuttings off the mature and 12/12 flowering plants, do so by week 2 at the latest and from the bottom of the plant. Label both mothers and cuttings and ditch what doesn't make the grade.

 

*heteroblastic development: the younger leaves of MJ are simpler with single to few lamina, often entire, or with little serration on the margin. Where as the older leaves will have several to many lamina and obvious serration on the margins. If you reveg a flowered plant by an increase in the photoperiod the lamina will start out single and entire and gradually build back up to their adult form. Many growers experience this if they wish to make a mother out of a trimmed flowered plant.

Edited July 12, 2009 by OrbitTime