Slipmatt

Hello all,

My las tgrow was something of a disaster, 5 seeds - 5 boys.. what are the odds!!?!

My question: does anyone know how early I could take a cutting to idenitfy the sex?? More importantly, would taking a cutting from a young plant, then flowering the cutting straight away work, or would the very young cutting just get stressed and go hermie anyway?

Come to think of it, would taking a cutting at the earliest opportunity simply stress the plant and ruin my young hopefulls??!!

There must be SO many more intelligent people than me here ( its not hard..) Any advice most welcome..

Thanks in advance,

Slipmatt

naturall_mystic

Taking a cutting isn't going to help you sex your plant earlier than the plant the cutting came from because it takes longer for a cutting to show sex than the plant it came from. The reason being, once the cutting is taken it has to grow its own root system, this slows down its progress a bit, all the while the host plant is still maturing. So the host shows it's sex first.

What you need to do is concentrate on providing an enviroment that is condusive to feminization. Here is how...

FEMININTY:
It’s what all growers want, we want those female plants. At least a high percentage of them. Growth of a male or a female plant from seed, except for the predisposition in the gender chromosomes, also depends on various environmental factors. Not only the origination of entirely male or female plants is partly affected by these environmental factors, the number of male and female flowers on a hermaphrodite plant is affected as well. The environmental factors that influence the sex of the plant (or the flower in the case of hermaphrodites), are among other things:

The quantity of nitrogen and potassium of the seedbed.
Humidity and moistness of the seedbed.
Level of temperatures.
Color of the light used.
Length of daylight.
Stress, any form of stress, causes more male individuals will originate from seed. Even the taking of cuttings from female plants may produce male or hermaphrodite cuttings.

To optimize the result, changes in one or more of the above-mentioned environmental factors for a certain period during growth, may be applied. During this time these environmental factors will deviate from the standard growing system for maximum harvest and quality, as described in nursery literature. The desired change(s) in the environmental factor(s) are started from the moment that the seedling has three pairs of real leaves (not counting the seed-lobes). This is the moment that male and/or female predisposition in florescence is being formed. After approximately two weeks the standard growing system can be reconverted to.

Of the 5 above-mentioned environmental factors the first three are the most practical:

1. Level of nitrogen and potassium of the seedbed: A heightening of the standard level of nitrogen makes for more female plants originating from the seeds. A lowering of the nitrogen level shows more male plants. A heightening of the level of potassium tends to show more male plants, while a lowering of the potassium level shows more female plants. A combination of a higher nitrogen level for the period of a week or two and a lowering of the potassium level is recommended.

2. Humidity and moistness of the seedbed: a higher humidity makes for an increase in the number of female plants from seed, a lowering for an increase in male plants. The same is valid for the moistness of the seedbed.

3. Level of temperatures: lower temperatures make for a larger number of female plants, higher temperatures for more male plants.

4. Color of light: more blue light makes for more female plants from seed, more red light makes for more male plants.

5. Hours of daylight: few hours of daylight (e.g. 14 hours) makes for more female individuals, a long day (e.g. 18 hours) makes for more male plants.

Now let's make some adjustments to that.. You can do whatever you want to your plants in seedling stage and early vegetative stage of growth (of course carefully)and it will not effect your final male to female ratios. The time when things should be near perfect is in or around the 3rd to 4th week of vegetative growth. This is the CRITICAL TIME for getting those female ratios up and up. Some plants become hermaphroditic because of problems that occur around this period of the plants development. If the problems occurred before this time there should be no hermaphrodism. The inherent genetics set in the seed has a massive impact on how this is expressed in the final phenotypic expression of the plants gender.

At the 3rd to 4th week of vegetative growth be sure that your plants are free from stress. No pests attacks, no fungi attacks, no mold, no irregular photoperiod, not under watered, not over watered, not pruned or topped, a cannabis friendly soil mix, not recently transplanted, no small pots. If the plants have these basic growing conditions under control then the manipulation of standard seeds to express female can begin.

N:P:K and nutrients. What this simply boils down to is that you have the right nutrients present in the right ratios. You nutrient formula needs to Have a higher N level than P and a higher P level than K. Fortunately most nutrient formulas manufactured for growing cannabis during the vegetative growth phase have these ratios. Also avoid overfeeding your plants around this time too as overfeeding causes plant stress.

Never let your medium dry out completely around the 3rd to 4th week of vegetative growth. If you make sure to water occasionally, but not to overwater your plants. Over watering or allowing the soil to dry out too much will encourage more male plants. Keep the soil moist, not damp.

Humidity. Now this is the tricky one. High humidity levels only promote fungi and mold development and lowering humidity levels is the way to cure most of this rot but by keeping those humidity levels up in or around the 70 relative humidity factor will help to produce more females. If you have a low humidity grow room then you should get to hold of a humidifier. Now high humidity levels like 70 relative humidity cause the medium to dry out a lot quicker so you got to keep this under control too. Keep those mediums moist and those relative humidity levels at 70. This will help to improve those female to male ratios. Again, getting them on the up and up.

If you run the 24/0 photoperiod then do not allow those temps to go anywhere above 85 unless you have an equatorial strain. 75 is the best but going a little lower is not a problem for helping those female ratios. If you can get in at around 65 then those females are going to be popping up all over the place. The problem with this is that some growers like to use the 18/6 photoperiod and when the lights are off the temps drop from around 65 to 50 and even less. Try not to be below 55 because this has the adverse effect on the plants producing more males than females. Again between 65 and 75 is where you want to be during the 3rd to 4th week of vegetative growth, the preference being 75.

Invest in a MH Light for vegetative growth. Dump the HPS bulb for flowering later. I have noticed that HPS lighting during vegetative growth simply sends those males to female ratios down. With MH lamps the females are everywhere. Invest in some MH HID lights. It makes all the difference in getting those females to show more often. This is worth repeating! MH Bulbs produce more females under optimal conditions especially if they are present during the 3rd and 4th week of vegetative growth. Surprising enough you can start seedlings under HPS and it will not have an effect on those female ratios. Again the 3rd to 4th week of vegetative growth is what is important here.

This isn't all my information and I don't know who to credit it to, but I do know it works as my last two grows have been all female. My first grow, before I read and followed the above, was 50/50.

Hope this helps, good growing.

__________________

Slipmatt

Ah! it's all so clear now..

Thanks for the help..

now, back to my 'special' cupboard with the light in it...

__________________
Tell no tales, leave no trails...

Quasi

very nice post..

st2

Based on your info when would you recommend starting some LST? Around week 5?

st2

1 more quick question. Based on your NPK info I am now questioning the use of Canna Terra. It's NPK is 3-1-3. However this stuff is made for the purpose of growing (by the Dutch nonetheless) and also has 1% MG and 1% Sulfur.

So would you say that this product might be good for growing but not great for helping to produce females? If so, what would you recommend?

Thanks for the good info.

WILL_Wants_WEED

all I would recommend is homeharvest.com for all your growing needs

__________________
NPK values of natural substances - http://www.primalseeds.org/kpnref.htm

stelow

Dutch Passion is who should get the credit, for a large portion of your post.

DUTCH-PASSION

__________________