There is no way to know before growing out a seed.
Wow, that is a really high ratio of males seed from a group of “regular” seeds.
The ratio is usually normally much closer to 50/50 in regular seeds that have been produced in the regular way, with pollen from a fully male plant applied to the buds of a fully female plant.
However, certain conditions. like a improper pH, over abundance of some nutrients,and photo period irregularities, especially interruption of the dark period, and other stresses, like heat stress may all contribute to poorer results. And especially in feminized seeds, will at least contribute to hermaphrodite flowers in your buds.
Many claim, even from regular seed you can dramatically increase the female to male ratio by carefully monitoring and adjusting the pH, and using certain light schedules and as well as using certain NPK ratios during specific periods of growth.
I found this from the guys that kind of “invented” feminized seeds.
Here it is for what it’s worth"
“Feminised Cannabis Seeds”
Courtesy of Dutch Passion
In November 1998 we introduced our “Female Cannabis Seed”. We did this after our own experiments showed that from female cannabis seed, we acquired almost 100% female off-spring.
In the meantime we are six months further on. We have received a lot of feed-back from our customers. The reactions are mostly positive! Clients have successfully produced almost 100% female off-spring. However there have been reactions from customers who found a few hermaphrodites or males plants.
Apparently environmental influences affect the sex of the female cannabis seeds as well. Because of the fact that Female marijuana seeds do not grow into female marijuana plants under all circumstances. Thus we changed the name from “Female Cannabis Seeds” into “Feminised Cannabis Seeds”.
From literature and from our own findings it appears that the growth of a male or a female cannabis plant from marijunaa seed, except for the predisposition in the gender chromosomes, also depends on various environmental factors. Not only the origination of entirely male or female marijuana plants is partly affected by these environmental factors, the number of male and female cannabis flowers on a hermaphrodite plant is affected as well.
The environmental factors that influence the sex of the cannabis 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.
Colour of the light used.
Length of daylight.
Stress, any form of stress, makes that more male individuals will originate from seed. Even the taking of cuttings from female cannabis plants may produce male or hermaphrodite cuttings.
To optimise the result, changes in one or more of the above-mentioned environmental factors for a certain period during marijuana 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 marijuana 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:
Level of nitrogen and potassium of the seedbed: A heightening of the standard level of nitrogen makes for more female cannabis plants originating from the weed seeds. A lowering of the nitrogen level shows more male cannabis plants. A heightening of the level of potassium tends to show more male marijuana plants, while a lowering of the potassium level shows more female marijuana 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.
Humidity and moistness of the seedbed: a higher humidity makes for an increase in the number of female cannabis plants from weed seed, a lowering for an increase in male cannabis plants. The same is valid for the moistness of the seedbed.
Level of temperatures: lower temperatures make for a larger number of female marijuana plants, higher temperatures for more male marijuana plants.
Colour of light: more blue light makes for female cannabis plants from seed, more red light makes for more male cannabis plants.
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 cannabis plants.