Sexing Cannabis: How to Tell the Difference Between Young Male vs Female Cannabis Plants
Are you growing cannabis at home, but aren’t sure if your plants are male or female? Then you’ve come to the right place! This article is going to show you how to tell the difference between male and female cannabis plants to properly sex them.
In particular, I want to show you how we determine the sex of our cannabis plants while they are still quite young. It gets significantly more obvious as the plants begin to mature and flower. On the other hand, it can be a bit more tricky to sex cannabis plants in the early pre-flower phase, but it is definitely possible! We’ll also talk a bit about why it is important to determine the sex of cannabis plants, the difference between regular and feminized seeds, how we treat our plants up until the time we know their sex, and what to do with unwanted male plants.
If you’re new to Homestead and Chill, be sure to check out our other cannabis-related articles! We primarily grow outdoors, 100% organic, and aim to provide helpful information that is easy to follow – both for new and experienced growers alike. As a disclaimer, this article is intended for those who can legally grow cannabis at home.
- How to Grow Organic Cannabis: Seeds, Soil, Containers & Care
- Organic Cannabis Pest Control: How to Keep the Bugs Off Your Nugs
- How to Feed Cannabis Organically: Top-Dressings, Teas & More
- How to Harvest, Dry, Trim, Cure & Store Homegrown Cannabis: The Ultimate Guide
- Sativa, Indica, & Autoflowers: The Difference Explained
- Vaporizing Cannabis: Science, Safety, Quality & Technology
- Tutorials on how to make homemade cannabis tincture, infused oil, or topical salve
Feminized vs Regular Cannabis Seeds
If you are growing from feminized seeds, you shouldn’t need to worry about sexing your cannabis plants all that much. While not 100% guaranteed, there is only a very slim chance that a feminized seed will produce a male plant. About 1% in fact. In all of our years growing, we have never had a cannabis plant grown from feminized seed turn out to be a male – though we only grow a handful of plants per year. Folks who grow hundreds of plants could potentially end with a rare male now and then.
Feminized seeds are highly desirable to most growers. They’re efficient. It is almost sure-fire that you’re spending your energy and resources raising ladies. However, some growers accept or even prefer regular (unsexed) seeds! We grow a little of both.
Why grow regular cannabis seeds? Well, maybe a particular breeder or strain you want to try only carries regular seeds. Some growers feel that the feminization process is unnatural, and prefer to kick it old school by growing regular seeds only. Some enjoy the gamble and challenge. Whatever the reason, when you grow cannabis from regular seeds, the odds of getting all lady plants are not in your favor. You will end up with some males. Therefore, you need to learn to sex your cannabis plants! Also, we always start several extra “regular” seeds – assuming a 50/50 chance that some will be culled because they are male.
How are feminized cannabis seeds made?
Curious about how feminized seeds are created? In a nutshell: most feminized seeds come from cannabis plants that have been treated and altered in a manner that inhibits male chromosomes. The most common method is to spray the plant repetitively (daily or more) with colloidal silver. Other chemicals and compounds can be used too, but are far less accessible. Colloidal silver is technically “non-toxic”, but you do not want to smoke it! Thus, the plant is sacrificial – used for the production of pollen and seeds only.
Repeated colloidal silver treatments cause repression of the plant’s ethylene, which is the stuff that creates male flowers. Instead, the treated female plant will grow pollen sacks full of FEMALE pollen (XX rather than XY). Then breeders use the female pollen to pollinate female flowers, resulting in the development of all-female seeds.
Another way to create feminized cannabis seeds is called rodelization. It is a more natural but unreliable method, and less frequently used by breeders. Near the end of a growing season, an un-pollinated female cannabis plant will sometimes produce pollen sacks in a desperate attempt to pollinate herself. That pollen can be used to try to create feminized seeds, but because ethylene hasn’t been repressed, may also result in male seeds.
Okay, back to sexing cannabis.
Why Sex Cannabis Plants? The Role of Male and Female Plants
For the most part, the average home grower wants female cannabis plants. The ladies are the ones that produce the fattest, most resinous and most potent flowers – aka buds. Male cannabis plants are only desirable if someone wants to breed cannabis and save seeds (which is a whole other topic for another day). Even then, the grower will want to spot the difference between the male and female plants and separate them early on, unless they want free cross-breeding and pollination between many types of strains.
Not only are the males less desirable, but male cannabis plants interfere with the quality and production of your female plant. Males grow pollen sacks, and produce pollen. When a female cannabis plant becomes pollinated by a nearby male, her energy shifts into producing seeds.
Like most things in nature, female cannabis plants have a biological drive to reproduce. After the deed has been done, she will sit back and relax. While a pollinated female cannabis plant WILL still develop decent size buds, they are usually lower quality and contain less THC and other desirable cannabinoids. Not to mention, they’ll be full of seeds. When left un-pollinated, a female cannabis plant’s flowers (buds) will continue to swell, develop more trichomes and become increasingly resinous. She is trying to get as sticky and large as possible to catch pollen in the wind. That sweet sinsemilla – aka unfertilized, seed-free cannabis.
When to Sex Cannabis Plants
Our goal here today is to learn how to tell the difference between male and female cannabis plants early on, so you can get the males away from the females as soon as possible! It will help protect your lady plants – but also spare you the wasted time, resources, and energy of tending to male plants that you don’t intend to keep.
Keeping in mind that every strain and grow set-up (e.g. indoors, outdoors, daylight hours) creates varying circumstances, most cannabis plants begin to pre-flower as early as 4 weeks after germination. By week 6, the pre-flowers begin to reveal their gender and you should be able to identify the sex using the tips to follow. Once the plants go into full flower (8 to 10 weeks on average, for a natural outdoor grow) the differences between male and female plants will be glaringly obvious. We’ll talk more about exactly what each sex looks like in a moment.
Until we can tell the sex for sure, we continue to treat the plants equally. We start our seeds in small 4-inch nursery pots. About two weeks after germination, we pot the seedlings up into an approximately two-gallon (trade size) “sexing pot” like these BPA-free nursery pots. This enables everyone to continue to grow in a happy and healthy manner for several more weeks*. Then, once we can surely tell the difference between the male and female cannabis plants, only the ladies move into their forever home – 15 to 25 gallon grow bags full of recycled organic living soil. To learn more about our soil recipe and how we maintain it, see this article.
*Note that our feminized seedlings go from a 4” pot to an 8” pot, and then more quickly into large grow bags, using less soil in the potting-up process.
How to Tell the Difference Between Male and Female Cannabis Plants in Pre-Flower
In order to correctly sex cannabis plants, you’ll need to become familiar with their anatomy in general. Both males and females produce pre-flowers and flowers in the junctions between stems or branches. The very first pre-flowers show up in the crook between the main plant stalk and a fan leaf stem (petiole), usually near the top of the plant. The good news is, the males usually begin to develop and show sooner than females. I guess the idea is that the dudes want to have their pollen ready and waiting for when the ladies join the party?
Look for plant pre-flowers at the higher stalk/branch junctions, as described above. If needed, use a jeweler’s loupe to get a better look! That is the same magnifying tool commonly used to examine trichomes and determine plant readiness for harvest. Then, locate the stipule, which is a leafy pointed flap that protrudes from the junction. Don’t confuse that for a pre-flower! The cannabis sex parts are located just behind the stipule. Behind the pre-flower sex parts, taller growth tips will emerge – future auxiliary branches that produce buds.
Identifying a Male Cannabis Plant
Very early, the male pre-flower (early pollen sacs) simply looks like a more round version than the female pre-flower part. It is often referred to as a “spade”, like the spade suit in cards – squatty with a bulbous bottom and very slight tip. As it becomes slightly larger, the male pre-flower resembles a ball at the end of a stick. The male pre-flower is called a staminate. Then, the staminate eventually develops into a long hanging sack of baby bananas – the pollen sacs. Hopefully you can ID and cull the males before they get to this stage.
Identifying a Female Cannabis Plant
In contrast, the very early female cannabis pre-flowers are more ovate in shape: pear-like, but with a longer slender pointed tip. That is called her calyx. Extending from the tip of the calyx may be a pair of pistils, or white hair-like protrusions. However, please note that not every female cannabis plant in pre-flower produces pistils.
If you are still unsure of the sex of your cannabis plant, wait to make any drastic decisions! Yet if you’re fairly certain, consider some of these other common differences between male and female plants. Perhaps it will help you more confidently make a decision.
Other Common Differences Between Male and Female Cannabis Plants
Aside from the clear-cut flower differences, there are a few (potential) trending characteristics between male and female cannabis plants. In many cases, male cannabis plants tend to be more gangly. They may be tall, narrow, have fewer fan leaves, and longer spacing between branches – also referred to as greater inter-nodal spacing. On the flip side, female cannabis plants are usually more compact and bushy than males.
Please keep in mind that these traits are not guaranteed, and shouldn’t be the only way to sex cannabis plants! Variations among strains and phenotypes can lead to all sorts of crazy things. The general plant structure simply may help give you a clue if you’re on the fence.
My Cannabis Plant is Male! Now What?
I hope you started a few extra seeds, and have plenty of ladies left to grow! Once you determine that you have a male cannabis plant, get rid of it. Again, unless you want pollination and seeds, it is best to cull the males as early as possible. Simply separating the plants isn’t enough. Even if you relocate the male plant to another part of your yard, the pollen can carry in the wind. There are stories of female cannabis plants becoming pollinated from neighbors growing several blocks away.
However, the culled males don’t need to go to waste! One option is to chop up the male plant and use it to mulch other plants – much like we do with borage, fava bean greens, yarrow, and comfrey. You could also juice the leaves, which are full of nutrients. Heck, you could even steep the plant material in water to create a natural fertilizer as we do with stinging nettle. Finally, I’m sure your compost pile will welcome the male plant with open arms. Or would that be… with open worms?
And that is how you determine the sex of cannabis plants.
In closing, I hope this article is interesting and useful in your homegrown adventures. Please feel free to ask questions in the comments below, and spread the cannabis sex love by sharing this article. Even if you like to grow mostly feminized seeds, don’t you find this stuff fascinating? I sure do. Thanks for tuning in and nerding out with me a bit. Best of luck this growing season!
72 Comments
Patrick Canavan
Good Morning, this website has been very helpful for a first time impatient grower. I’m well into the eighth week with plenty of healthy growth. Still cant tell sex but feel im getting close. Didi I mention impatient! I topped and fimmed with good results, my question is should I have waited until the sex was determined to do that? Fingers crossed I didn’t mess up and impatiently waiting. Ps. all outside. Thank you!
Aaron (Mr. DeannaCat)
Hi Patrick, it’s great to hear you are growing some healthy plants thus far and that you have found the website helpful! Sounds like the strains you are growing are just taking their sweet time to show their sex, last year we had one plant that got close to 5 feet tall before we knew what sex it was. You should be good to go with your topping and fimming as it doesn’t sound like the plants lost any luster do to it. Hope that helps and good luck on your outdoor season!
David Chisholm
Hey y’all,
Loving the site and articles/posts! The absence of pretence and genuine joy is refreshing. The post about growing and building your own soil was so inspiring, I’ll be doing that this spring. Here in Toronto Canada so no issue with legality 🙂 The thought of getting my hands in the dirt this spring is making the winter bearable 😉
Two quick opinions sought; I only have regular seed (Jack Herer, Apricot Kush and Pink Mango) are the plans for this season. Given that I have to germinate, then sex them, would you recommend germinating 3 or 4 seeds of each strain? Ideal would be one plant of each strain when all done, but if I have say two of one particular strain, that’s certainly not the end of the world 😉
Really want to ensure I’ve covered my bases as the growing window here in Canada is tight so having to re-germinate after losing six weeks would be devastating.
Keep up the great work you two! Fan in Toronto.
David
Aaron (Mr. DeannaCat)
Hi David, thank you so much for the kind words and we appreciate your support of Homestead and Chill! It’s great to hear you are looking forward to building your own soil, it will make such a big difference when it comes to your plants health. With regular seeds, there can really be a wide ratio in M/F plants depending on the seeds themselves, as a whole, it should more or less be a 50/50 ratio over time. If I sprout 12 regular seeds, I am typically looking for 6 females out of the lot, however, I have had times where I ended up with 8 females out of 12 seeds, other times only 4 females out of 12 seeds. I think sprouting 4 seeds of each will give you the best chance at least getting one female plant for each strain, if you end up with more females than needed, you can always keep the one that looks best to you and cull the other. If you are flush with seeds, you can always sprout a few more just in case, but out of 12 seeds, you should be able to get 3 females. Hope that helps and keep us up to date on your progress. Good luck and have fun growing!
Eric
Hey guys, I appriciate your article. I am 1st time grower and I’m one day away from 6 weeks (indoor) and I still cant tell the sex. I have 1 indica and 2 sativa (one is like a bonsai and the other 2 are growing tall and lanky). I am thinking about flipping them soon and I was wondering if I should sex them 1st? Also when I flip should I get my other plants out of that grow room? I have young tomatoes and potatoes in the tent too (1st time on those too.)
Thanks,
Eric
Aaron (Mr. DeannaCat)
Hi Eric, some plants take longer than others before you can tell the sex but chances are you should be able to tell their gender before too long. You can flip the light schedule on your plants if they are in their final container and you have the space, you can always cull or figure out what you want to do with any male plants that may show after you flip. In our indoor grow space we use a 4×4 raised fabric bed, so I always try and sex the plants before they end up in the bed so I don’t have to remove plants later.
Now, whether you want to keep your potatoes and tomatoes in your grow space will depend on how much space you have and which crops are a priority for you. I don’t see any harm in growing tomatoes or potatoes with 12 hours or less of light, but again, not sure about the amount of space you have to work with or what your plan was with the vegetable plants in general. Hope that helps and good luck!
Jamie
Can you share more about the indoor fabric raised bed? I’ m planning an indoor tented grow and still gathering supplies for my setup. I was thinking grow bags, but an intrigued by this idea.
Aaron (Mr. DeannaCat)
Hi Jamie, Grass Roots, GeoPot, and Dirt Pot are all companies that sell a variety of different sized raised fabric beds, we have a tan Dirt Pot 4×4 raised bed which actually measures closer to 46×46 inches (just shy of 4 feet) and 12 inches tall. To collect whatever runoff that might occur, although I try and keep that to a minimum so there isn’t standing water, I found a Botanicare Low Tide 4×4 tray (measures closer to 47.5 inches), filled it with a small amount of 3/8″ volcanic rock on the bottom for the raised bed to sit on. Lava rock helps soak up water and I figure the raised bed will slowly wick up whatever moisture is present in the rock. We also have the tray and raised bed sitting on two heavy duty furniture dollies so we can still move the raised bed if needed.
We originally went this route because we would have to sex plants indoors in 2-2.5 gallon pots before up potting them into 5 or 7 gallon grow bags for flower and the doubling or just over of a pot up was kind of a pain to do as the root ball was not too much smaller than the pot we were trying to pot up into. We still sex plants in the 2 gallon pots and just sit them on the top of the raised bed soil until they get transplanted into the bed. Anyway, we typically try and have close to 6 females to plant into the 4×4 bed with some topping and LST. It just really depends on how many plants you want to grow and how big you want to grow them, your options are really endless. Hope that helps and good luck with your new grow set up!
Rudolph
In the old days I would acquire cannabis with plenty of seeds to smoke so I’m presuming it was male yet euphoric , is that the case?
Aaron (Mr. DeannaCat)
Hi Rudolph, much of the cannabis from the older days that you are referring to was still female flowers, the people growing the plants just didn’t separate the males from the females so the plants were often pollinated, resulting in cannabis flower from female plants with seeds in them due to the presence of the male plants during the growing process. Hope that helps and good luck!
Joe
Thanks for the 411
Greg Gautier
Such detailed info, thanks!!! How old would a male plant (standard outdoor growing) need to be, before he starts “sowing his oats” all over my beautiful innocent ladies?? 😂
Aaron (Mr. DeannaCat)
Hi Greg, it depends on the strain but they typically flower quicker than female plants so their pollen is ready once the female flowers are ready for it (around 3-4 weeks of flower). If you want to cull the males and not create seeds, you will have more than enough time to get rid of the male before it starts releasing pollen. Hope that helps and good luck!
zachery sandefer
just apollenated female most likely
josh
3 out of my 6 plants are for sure female and they are my largest ones, 2 taller than me and im 6 foot, and the other one probably 5 1/2 and super duper bushy which is funny because i never topped them. I am still having trouble identifying the other 3. 2 are super bushy and the other one is taller but also thick and not gangly. they werent from feminized seeds. im just going to keep a close eye on them. they look identical to my 3 females. my other three GSC in the other garden are for sure female because the seeds were feminized and they showed their sex months ago. Praying they turn out female. I put a lot of blood sweat and tears into these plants and they turned out better than i expected. Seeing this is my first time growing i am pleasantly surprised. A lot of studying has gone into this and using all natural fertilizers like nettle tea and fish emultion, banana water, mollasses, epsom salt, ashes, calcum ect ect has really turned them into some amazing plants. The soil ph is also perfect. it also helps that i have a horse so i have plenty of horse poop. Your site has helped a lot and i thank you for that. Next year is going to be a good year and done differently. this was just a test year. i put them in the ground as seedlings on april 30th. today august 2nd they are anywhere from 5 to 6 1/2 feet. next year im starting them in feburary in the green house.
Sylvain Ferron
Vessy seed are the best 👌 seed i use yet.
Greg Gautier
Strange you still can’t judge their sex given they are obviously quite mature? Would have thought by the time the 3 6ft ones were that size, if there were any males they would have made your ladies seedy by now??
Aaron (Mr. DeannaCat)
Hi Greg, sometimes it can be quite hard depending on the strain and specific plant. We had a plant this summer grow to at least 5 feet tall before it showed any sex organs outdoors and it ended up being male. I am not positive but it seems like the genetics I have grown, with origins from near the equator, seem to take longer to show sex. And as far as pollen goes, by the time a male is actually ready to release pollen, you would know for sure of its sex as it will be covered in male flower clusters which drastically differ in appearance compared to female flowers.
Bear
First time growing, several weeks old and I’m.still second guessing male and female. The preflowers are a purplish color. Elongated balls but don’t see any pistils?
Is there a way to post pics?
Aaron (Mr. DeannaCat)
Hi Bear, unfortunately our site doesn’t allow picture uploads in the comment section. If your plants are only a few weeks old, you likely can’t tell the sex of the plants anyway. If you are growing indoors under a grow light, most plants seem to sex by the 5th week or so. If you are growing outdoors it seems they can take a little longer, this is also strain dependent as some show sex quicker than others. Once the preflowers are more visible, you will be able to tell the difference. Good luck and have fun growing!
Chris Acker
Hi Aaron,
We have boys! Just wanted to let you know that we went away for a few days and returned tonight to find our plants had all exploded in growth. They are all females. Thanks for your guidance.
Best,
Chris
Chris
Hi guys,
I first found your site looking for worm composting. Love all of your content and we have shared it around to family and friends.
This year I decided to grow Cannabis for the first time ever. I have Maui Wowie and Chem Dog, both feminized. 3 plants each. I germinated the seeds in early March and potted them in early May 22 in 5-gallon grow bags. I’m topping all plants and, while I want high yield, it’s just me and I don’t need 6 lbs of product. I still focus on my tomatoes.
Anyway, I feel like my plants are behind in the growing cycle. They look beautiful and healthy, but I can’t see sex organs yet. they’ve been in veg since 3/23/2022. I’ve got all the right elements – soils, nutrients, space outside, and direct sun exposure.
Any thoughts on this would be helpful. I guess I’m just impatient.
Thanks again for your very thoughtful and well-written content.
Best,
Chris
Aaron (Mr. DeannaCat)
Hi Chris, so glad you found us and are sharing our site with friends and family, we appreciate the support! How were the roots on your plants when you transplanted them into 5 gallon bags? Not sure if they were stunted slightly if they were root bound or not? If they are feminized seeds I would likely have them in their final pot or container by the time they have grown 6 nodes which usually occurs within 4-5 weeks or so. You will likely need to get them into 10-15 gallon bags at the very least for them to finish their flowering cycle happily. Also if they are feminized seeds, no need to worry too much about seeing their pre flowers as if they are from a reputable breeder, chances are around 99% that they will be female. In all, if they look healthy, I wouldn’t worry too much about it and just let them do their thing. Hope that helps and have fun growing! Reach out if you have any questions in the future.
Chris
Hi Aaron,
Thanks for the reply! These plants are/were very healthy when I transplanted them. I guess my concern is that I see all these beautiful plant photos online and I’m just seeing vegetative material in mine. They look great and I’ve topped them and cared for them as I care for our tomatoes, IE I baby them. I think I’m just impatient.
As for the 5-gallon grow bags, are you saying I will need to triple the size? I was hoping this could be their final resting spot. What would happen if I didn’t pot up? Again, I’m the only consumer. I showed some photos to my nephew who went to UCSB. The first thing he said was, “wow, Uncle Chris, that’s a ton of pot for one guy”. So, yield is not that important. Quality is very important.
THoughts?
Chris
Aaron (Mr. DeannaCat)
Hi Chris, it sounds like you are doing a great job and the plants won’t typically start to flower until mid summer or so, unless they start receiving less than 12 hours of sunlight before then. Even in areas I have grown outdoors where the plants never received 12 hours of light at all, they still typically grew in a vegetative state for at least 8 weeks before they started flowering.
I recommend at least 10-15 gallon containers outdoors (I like to use 25 gallon grow bags) because it allows for more room for roots, growing in a 5 gallon container will require more maintenance and the plants will need to be babied more (i.e. watered a lot more…). If it gets hot where you are located, the plants will need to be watered much more often than if they were grown in larger containers. The plants overall will be much happier in a larger container.
And yes, 6 plants if grown through their full cycle outdoors will produce a huge harvest. You may have to get creative and give some away to friends and family, you can also make salve, oil, or tincture. Hope that helps and good luck!
Heather Edens
My plants are 3 weeks old and I can’t tell the difference in them is 2 of them are taller and smaller leaves. The other two have big leaves and seem shorter. I got my four seeds from saving out of my bags for the year lol.
Aaron (Mr. DeannaCat)
Hi Heather, your plants are still too young to know for sure if they are male or female but within the next month or so they should reveal themselves. There is also usually some variability in the seeds or offspring of the parent plants where there are typically a number of different phenotypes found in any given strain. Hope that helps and good luck with your plants!
Sierra
I was given a plant about to show its sex, and I’m also about to pot some feminized auto flowers. If the gifted plant is a male, can it/ will it pollinate my feminized autos??
Aaron (Mr. DeannaCat)
Hi Sierra, yes it can pollinate the female autoflower plants. If you don’t want the plant if it turns out to be male, you will have plenty of time to remove it before it starts to drop pollen and pollinate any nearby female plants. Hope that helps and have fun growing!