Cannabis Hermaphrodites, Stress Testing
Cannabis Hermaphrodites are no fun to work with and could seed your whole crop.
The goal of a cannabis pheno hunt isn’t just to find plants with outstanding qualities it is also to find sexually stable phenotypes. Therefore, stress testing is one of the most important parts of every successful pheno hunt. Whether you are a commercial growers, a hobby grower or a breeder, working with pure, sexually stable females will turn out to be crucial.
In this tutorial we’ll first debunk some of the myths surrounding cannabis hermaphrodites. Then we will go over some useful tips on how you could effectively stress test your cannabis plants.

I Cannabis Hermaphrodite Myths
Myth 1: Feminized Cannabis Plants Aren't As Sexually Stable As Regular Cannabis Plants
Myth 2: Cannabis Hermaphrodites Are Rare And Most Cannabis Plants Are Sexually Stable
Myth 3: Hermaphroditism Is Due To Stressful Growing Conditions
No matter how skilled you are at tending your garden you are always at risk of having some of your plants herm. This is because hermaphroditism is already present within the plant’s DNA. Although stressful conditions cause most plants to reveal their intersex tendencies, highly sexually stable plants will not herm even when under stress.
Myth 4: Landraces And Wild Cannabis Varieties Do Not Herm As Much As Modern Strains
It is quite the opposite. For many landraces and wild plants, having the ability to turn hermaphrodite is a survival mechanism. It allows the plants to reproduce even when there are no males or females around.
As hermaphroditism is an undesirable trait, many modern breeders have helped increase the sexual stability of most modern cannabis strains.
II Stress Testing Tips
Here are 7 simple tips you can easily apply in order to force your plants to reveal their hermaphroditic tendencies:
1. Grow Your Plants Indoors
Outdoor plants almost never show their hermaphroditic tendencies. However the same plants grown indoors could easily grow some “nanners” or “ball sacs”.
That is because indoors, the light spectrum isn’t the same as the sun’s. Likewise the root ball of the plants is at room temperature whereas outdoors, it is often cooler than the air. The light cycle and the soil composition are also different. All these factors cause a lot of stress to the plants thus explaining why plants herm much ore often indoors.
2. Use Small Containers For The Entire Life Cycle
3. Raise The Temperature Of Your Grow Room
4. Give Your Cannabis Plants Too Much Nitrogen
5. Over/Under Water Your Plants
6. Let Your Cannabis Finish Under 24 Hours Of Daily Light
7. Let The Plants Flower Past The Harvest Date
III Frequently Asked Questions
How To Stress Test Auto Strains?
How Many Plants Should You Grow?
What Is The Best Way To Spot Cannabis Hermaphrodites?
Here is a great tool you can use to easily spot the Hermaphrodites, the Headlamp! It is cheap and very effective. Inspect your plants in the dark to make the sneaky male flower stand out from the female floral clusters.

Preventing Hermaphroditism
If you can only grow a limited number of plants and are looking to do a pheno hunt, then you should avoid all types of stress.
Do the opposite of what we talked about in this tutorial and your cannabis plants will be much less likely to herm.
Really interesting article! Very informative, thank you.
It worries me that yours is the only easily accessible article I found on this subject. If you are the only person writing about it, how can we be confident that adequately stress testing new varieties is a common practice among reputable seed banks?
Hello Benjamin,
It’s one of the main reasons why we got into breeding, because it was rare to find strains that are truly sexually and genetically stable.
Some breeders do all their breeding outdoors and others sometimes hurry to get their new trendy “strains” to market without putting in the work (Stress tests and stabilization of the lines) while others completely decentralize their seed production.
Fortunately, there’s still some serious breeders out there such as ACE, Ethos, DJ Short… but it is a minority.
Thank you, I am glad you found the article interesting!!
Best,
Al & the Khalifa Team
Hi,
I have what is presumed to be a male plant sourced from a consumer product. I would like to make it herm. I want to do that because I don’t think I could ever find this strain again. Can one effectively get pollen from it, and subsequently stress it into producing seeds? Then I could plant a seed and pollinate it with itself, no? I plan on at least collecting pollen to keep it around in some form.
Thanks,
D
Hi Dennis, that’s a great question!
There are 2 ways to go about it:
1- By using an Ethephon spray, you can increase ethylene production and cause a male plant to produce female flowers.
2- By backcrossing many times to that male, the offspring will be genetically very similar to the strain you are trying to preserve.
Cheers,
Al & the Khalifa team