Growing from seed, male or female?

When one grows from seed, and the seed is not feminized, there is 50:50 chance of male flower. As far as I understand, the grower can not tell the difference between male and female until progress to flower. Am I right? I know that some growers tell females are so distinct, for example they are bushier. Is that true?
I think one should send samples for test for example using GreenScreen Plant Sex ID Kit to be 100% sure and not wasting time by taking care of a potentially male plant all the way through flowering. I appreciate if you share your experience with me.

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It usually takes at least 8 weeks for a plant grown from seed to reach sexual maturity and begin to demonstrate distinct signs for male or female. That being said, there are traits that can be shown earlier that may signify sex but they are not absolute and are unreliable means of making gender determination.

I am not familiar with the GreenScreen Plant ID Kit. Do any @mastergrowers, @CAMasterGrowers, @growopowners, @CAgrowopowners, @Caregivers, or @GrowOpEmployees have any insight into this product?

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Can you please explain more on the distinct signs and traits for male and female.

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The male plant will resemble a pawnbrokers ball and will first show at the internode where the stem meets the branch. It will look much different than the female flowers we growers are so accustomed to seeing. I will pull a pic from the internet to show you a male flower as I don’t allow these guys to grow in my garden!

image

If you see anything that looks like the above image (including in your female flowers as this is an indication of hermaphroditism), KILL IT, unless you want seedy buds

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Thank you for the reply and detailed explanation. But you will see that feature when you change the photo period and start flowering stage. Am I right? Is there a way to tell the difference in the vegetative cycle?

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@nick

I love the image!

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never used GreenScreen personally. Ive used Phylos and always been happy with their service as its quick, meant to be done as soon as the seedling has germinated (lowest wasted amount of inputs/$), and they help identify plants that are more susceptible to flipping genders or herming out.

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For fastest results, using something like Phylos is very effective and will save you time and maintenance costs despite the cost up front. They claim 100% accuracy, and hermaphrodites will be determined as “male.” But if you don’t mind waiting a little while (as GrowerNick mentioned, about 8 weeks), you can practice and start to become very accurate at predicting sex before making the switch to flower. Some strains can be identified in under a month, but this depends a lot on genetics. Anyhow, you should be able to find premature flower parts behind many of the bracts within individual branch nodes. Pistillate and staminate parts have a slightly different look. It’s subtle, but if you make educated guesses, and then send your plants to flower to verify your guesses, it’s not too hard to get near 100% accuracy. Describing the the difference in parts is difficult in text (and they are very small), but you can find some good pictures if you search the web. You might need a magnifying glass in some cases. And I would like to reiterate the point that you will definitely make incorrect guesses if you base it on any other growth characteristic like height, leaf shape, etc.

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Phylos is a great service as is Strainly. I am going to call @Strainly in to this conversation to hear his two cents on the matter. Thanks for the great post, @Jacob. Let me know when you want to burn down another monster bat! :wink:

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I like both of the suggestions made here by @Cody: you can never go wrong with the accuracy offered with genetic sequencing, but also, honing your skills as a grower by doing some predictive analysis. One thing I love about @fdousty, is she is always thirsty for knowledge and is here to learn. I appreciate that @Cody not only took the time to respond with something very meaningful, but also implored that growers continue to hone their craft. This is a sign of a master grower in my book!

Also, every grower needs to invest in a good loupe or magnifying glass or camera! These handy devices should never be more than arm’s length away from you at all times in your grow!

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You may need sex test if you always start your grow from regular seeds (not feminized). If you start from fem seeds, you should be safe.

However, you may quickly want to start your grow from clones in order to shorten the veg period and ensure you know what you are growing (since you know the mother).

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Thank you for the great explanation. That answered my question. My plants are not very young, I think I should be able to look for those premature parts. I will update here on my findings and hopefully some photos. and regardless, I will send them for Sex ID.

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Thank you Nick! very well said on continuous need of developing growing skills and predictive analysis.

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@Cody @Growernick @Jacob I took some photos.
I have two plants:
Plant # 1: Could be female?



Plant # 2: Could be male?

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Based on this guide:


Source: https://www.spliffseeds.nl/sex-determination-after-planting-marijuana-seeds.html

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I would say they look female based on those pictures. Straight males have pods that come grouped similar to grapes (ill see if i can find a good picture online). It could be a male hermaphrodite but I cant really see if there is a pod on plant two cause the photo is a bit blurry.

When unsure its most important to continuously check unless you think the plant is old enough for pollen sacs to start opening, then I would say play it safe and toss the plant before it can pollinate the rest of your crop.

The guide above is a good visual representation of what to look for. Male parts will be more bulbous and will not have the pistil coming out of the calyx. Beware of using just one site of sexual identification! Plants can have pistils down low and pollen sacs up high (and vice-versa) if a plant herms out so check the whole plant for pollen sacs regularly.

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Found a picture online that should help:

This comparison shows early signs of both genders. Look closely at the male example and you will see the pollen sacs are not open yet.

If the male/female plants are the same age in this photo and grown in a controlled light environment I’d say their about the end of Flower week 2.

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This is an incredible thread. Thanks everyone for truly sharing some expertise on early gender identification and demonstrating the level of care, with a keen eye, that’s required to really excel in the industry.

I’m always looking for new ways to improve the supergrower system, and this thread has me considering the values of being able to track plant gender specifics through the plant lifecycle. Not to pivot too much, but has anyone here noticed certain metrics or data that you think would be extremely beneficial to track regarding plant gender or related considerations? (I can see this being a contributing factor to waste if you have to destroy a plant that’s herming out).

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Thank you Jacob! I did not know about the importance of grouping of pods in straight males. and I am sorry for the bad quality of photos. My plants are still in the vegetative phase, so it could make it harder. I sent samples of both plants for Sex ID yesterday. I will post the lab results here.

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Unfortunately I have no hard data that I can share. However we have seen that strong, stable, genetic lines are the biggest factor in preventing herms. Environmental stresses (heat, oversaturation of light, EC, etc.) are obviously a big factor as well, but the best metric I can think of for a grower to reduce the # of hermed plants is to talk to your genetic source and find the one that backcrosses their strains the most BEFORE putting them out on the market.

A reference for those that go this route; in commercial agriculture its standard for seed companies to go through a minimum of 9 generations before introducing a new cultivar into the market. This is what helps to ensure every tomato plant produces an almost identical tomato despite the plants coming from multiple seeds.

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