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Early signs of hermie plant: Spot hermaphrodite cannabis fast
A hermie cannabis plant can ruin your entire grow in days.
If you don’t act fast, you risk losing months of work to accidental pollination.
If you don’t catch the early signs, male pollen sacs will burst, pollinating your female plants and leaving you with seedy, low-quality buds instead of potent flower.
But don’t worry; now you’ll learn how to identify early signs of hermaphrodite cannabis plants, what causes them, and how to prevent them from wrecking your harvest.
Disclaimer: Any information given on this site is for educational purposes only. Please ensure if you’re growing cannabis, you’re doing so by the law and subject to appropriate permissions and licenses of the applicable country.
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What Is a hermie cannabis plant?
A hermaphrodite cannabis plant develops both male and female reproductive organs, meaning it can produce male flowers while still growing female flowers
Mixed sex plants are capable of self-pollination, which leads to seedy buds instead of high-quality, smokable flower.
Most growers aim for female cannabis plants that produce potent, seedless buds, but hermaphrodite cannabis plants disrupt this process by accidentally pollinating nearby female plants, ruining an entire crop.
Mixed sex plants can emerge due to genetic predisposition or plant stress caused by environmental factors such as light leaks, unstable light cycles, extreme temperatures, or poor growing conditions.
These stressors can trigger the plant to develop male reproductive structures as a survival mechanism, ensuring reproduction by creating seeds rather than focusing on flower production.
Types of hermaphrodite cannabis plants
There are two main types of hermaphrodite plants, and knowing the difference can help determine the best course of action.
True hermaphrodites
These plants naturally develop both male and female sex organs on different parts of the same plant.
This is usually due to genetics rather than external stress.
Some strains, especially feminised seeds that weren’t properly stabilised have a higher likelihood of hermaphroditic tendencies.
Stress-Induced hermies
This occurs when a female cannabis plant experiences extreme stress, triggering it to develop pollen producing sites and both male and female reproductive organs.
Common causes include dark cycle disruption, irregular light cycles, heat stress, or physical damage.
The majority of growers will remove any hermaphrodite plants immediately to prevent unwanted pollination and protect their crop.
Since hermaphrodite cannabis plants can still produce buds, some growers attempt to remove both male pollen sacs and mixed-sex buds to salvage part of the plant.
However, this is risky, as even a single missed pollen sac can lead to accidental pollination of female plants, reducing flower quality.
For most cultivators, removing hermaphrodite plants is the best way to avoid ruining an entire grow room.
Early signs of hermie cannabis plant
Spotting early signs of hermaphrodite weed is crucial for cannabis cultivation success.
1. Pre-flowering sage inspection
The pre-flowering stage is the best time to catch potential hermaphrodite plants before they develop both male reproductive structures and female flowers.
This is when plants begin to show early signs of their sex, making it critical to check for hermaphroditic tendencies.
Signs to look for:
- Male flowers forming at the nodes instead of clear female reproductive organs
- Clusters of small, round growths appearing where pistils should develop
- Unusual flower development, particularly in plants that previously showed female characteristics
If you notice both male reproductive structures and female flowers forming, your plant is likely turning hermie. Female plants nearby should also be checked to ensure pollination hasn’t occurred.
2. Male pollen sacs formation
A hermie cannabis plant doesn’t always reveal its hermaphroditic tendencies immediately.
Some plants will seem healthy and fully female until male flowers appear later in the flowering stage.
How to spot them:
- Small, smooth pollen sacs forming deep inside buds
- Banana-shaped structures (nanners) emerging from flowers
- Clusters of male flowers grouped together, typically found near the plant’s nodes
3. Unusual flowering patterns
A hermaphrodite cannabis plant often exhibits mixed sex buds, meaning both male and female reproductive organs appear in the same bud site.
Key differences:
- Female flowers have white pistils, whereas hermaphroditic plants have both male sacs and pistils
- Buds may appear normal at first but later develop pollen producing sacs
- Sacs forming within the same flower structure is a sign of advanced hermaphroditism
Why early detection is critical
If you spot hermaphrodite tendencies early, you have a better chance of protecting the rest of your flowering plants.
The key is to inspect your plants daily, especially if they have been exposed to stress factors like light contamination, unstable light cycles, or extreme temperatures.
While some cannabis strains have a natural genetic predisposition toward hermaphroditism, the most common cause is stress.
Cannabis plants are particularly sensitive during their flowering stage, and any environmental instability can trigger a stress response.
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Causes of hermaphrodite cannabis plants
1. Light leaks and light cycle disruptions
Why it happens
Light consistency is one of the most critical factors in a successful grow.
Cannabis plants have a strict photoperiod, meaning they rely on uninterrupted dark periods to properly transition and remain in their flowering stage.
Any photoperiod disruption or sudden disruptions in their schedule can interfere with their hormonal processes and cause them to go hermie.
Here’s how:
Confused hormones
Cannabis plants produce flowers in response to changes in light exposure. During the vegetative stage, they thrive under 18+ hours of light. However, when switched to 12 hours of darkness, the plant understands it’s time to flower. A light leak during the dark period can cause the plant to revert to a confused state, increasing the chance of stress-induced hermaphroditism.
Interrupted flowering phase
If the plant suddenly receives light during its dark cycle, it can panic and develop male flowers to protect itself.
Grow room light pollution
Small cracks in tent zippers, LED indicator lights, or even a brief accidental flick of a grow room light can be enough to stress the plant.Prevention tips
Check your grow space for light leaks
Even small leaks can cause problems. Step inside your grow tent or room during the dark cycle and let your eyes adjust for a few minutes. If you can see any light, it’s too much for your plants. Use blackout material or tape to cover any leaks.
Keep a consistent light schedule
Set up reliable timers for your grow lights to ensure they turn on and off at the same time every day. Avoid manual light switching, as even small inconsistencies can cause stress.
Avoid turning lights on during dark periods
Never interrupt the dark cycle unless absolutely necessary. If you must enter the grow space, use a green LED light, which cannabis plants don’t detect as a light cycle disruption.
2. High stress from pruning and training
Why it happens
High-Stress Training (HST) and Low-Stress Training (LST) are common techniques to manipulate plant structure and improve yields.
However, excessive or poorly timed training can trigger hermaphroditic traits.
Too much stress, too fast
Cannabis plants need time to adjust to stress. Snapping branches, overbending stems, or applying excessive LST at once can send the plant into survival mode.
Aggressive pruning in flowering
Removing too many fan leaves at once - especially during flowering can shock the plant. The plant perceives this as a survival threat and may produce male flowers as a backup mechanism.
Topping and FIMing during flowering
These techniques are great during veg but should never be performed when the plant is already flowering. Cutting the top off a flowering plant creates extreme stress, which may lead to hermaphroditism.Prevention tips
Train plants gently and gradually
Instead of bending multiple branches at once, perform LST over several days. When super cropping, always support the stems to prevent unnecessary breaks.
Avoid aggressive pruning in the flowering phase
Plants are limited in their ability to recover from wounds when in flower. Remove only yellowing or blocking leaves and avoid large-scale defoliation.
Plan HST techniques early in veg
If you’re using topping, FIMing, or mainlining, do it before the flowering phase. Once buds start forming, let the plant focus on producing flowers rather than healing wounds.
3. Extreme temperatures and humidity Issues
Why it happens
Cannabis plants thrive in a specific temperature and humidity range, and going outside this comfort zone for prolonged periods can lead to stress-induced hermaphroditism.
Extreme heat (above 30°C / 86°F)
High temperatures can degrade essential plant hormones and increase ethylene production, which may force the plant to produce male flowers as a survival mechanism.
Cold stress (below 15°C / 59°F)
Cold can slow down plant growth, shock the root zone, and trigger stress responses, leading to hermie traits.
Low humidity (<30%)
Extremely dry conditions (high VPD) can cause plants to close their stomata, leading to water stress. Plants experiencing drought-like conditions are more likely to hermie in response.
High humidity (>70%)
Excess moisture (low VPD) can create mould risks, leading to fungal infections that stress the plant. If the plant senses it’s under attack, it may try to reproduce quickly by developing male flowers.Prevention tips
Keep temperatures between 20–26°C (68–79°F)
Use fans, air conditioning, or heating elements to stabilise the temperature in your growing area. Keep thermometers at canopy level for accurate readings.
Maintain stable humidity levels. For optimal growth:
- Veg stage: 40–70% humidity
- Flowering stage: 40–50% humidity
- Late flowering: 30–40% humidity (to prevent mould)
Use a humidifier or dehumidifier to keep conditions stable.
Ensure proper air circulation
Good airflow helps prevent hot spots and humidity fluctuations. To keep conditions even, place oscillating fans above and below the canopy.
Prevent stress-induced hermaphroditism with the Grow Sensor
The Grow Sensor is a cutting-edge grow room monitor that provides real-time data on key environmental factors.
Whether you’re a hobbyist or a professional grower, it ensures that your plants stay within the optimal temperature and humidity range, minimising stress and reducing the risk of hermaphroditism.
Key benefits of using the Grow Sensor:
- Real-time environmental monitoring – Tracks temperature, humidity, and VPD (vapour pressure deficit) to maintain the ideal climate for healthy flowering.
- Light consistency assurance – PPFD and full-spectrum PAR sensors continuously measure light intensity, helping prevent photoperiod disruptions that can lead to hermaphroditism.
- Soil and root health tracking – Monitors soil moisture, electrical conductivity (EC), and root temperature, ensuring optimal nutrient uptake and reducing stress-induced issues.
- Instant alerts and trend tracking – Custom notifications via an intuitive mobile app for iOS and Android help growers detect and respond to environmental shifts before they cause problems.
By integrating the Grow Sensor into your setup, you can eliminate guesswork, fine-tune your grow conditions, and dramatically reduce the risk of stress-related hermaphroditism.
Consistency is key to producing high-quality, seed-free cannabis, and with real-time data at your fingertips, you’ll always be one step ahead.
4. Poor genetics or low quality feminised seeds
Why it happens
- Genetic predisposition: Some strains naturally carry hermaphroditic genes.
- Low-quality feminised seeds: Some poorly bred feminised seeds are produced using chemical stress methods, making them more likely to turn hermie under minor stress.
Prevention tips
Buy high-quality cannabis seeds from reputable breeders
Reputable breeders select stable genetics that are less prone to hermaphroditis, and there’s less chance you’ll have to deal with male plants.
Research strains before growing
Some strains, especially landrace Sativas, are naturally more prone to hermaphroditism. Choose strains with strong, stable genetics to minimise risks.
What to do If you spot a hermie plant
Finding a hermaphrodite plant in your grow can be frustrating, but quick action can help prevent pollination and save your harvest.
Once you spot a hermie, you have two main options:
1. Remove hermaphrodite plants immediately
If the plant has many male flowers, it's safest to remove it from the grow space immediately.
Leaving a full hermie plant in the grow risks pollinating all female plants in the proximity, leading to a seed-filled harvest.
Always bag the plant before removing it to avoid spreading pollen in the air.
When to choose this option:
- The plant has clusters of pollen producing sacs rather than just a few.
- You are growing multiple plants and don't want to risk pollination.
- It is late in the flowering stage, and removing sacs manually would be too risky.
2. Carefully remove pollen sacs
If your plant only has a few sacs, you can attempt to remove them manually.
Use sterilised tweezers to pinch the sacs off before they open.
Applying a little water to the sacs before removal can reduce the chance of airborne pollen.
Check your plants daily, one missed sac can lead to pollination.
When to choose this option:
- Only one or two small sacs are visible.
- The plant is otherwise healthy and producing dense buds.
- You are growing just one plant and want to avoid removing it entirely.
If pollen spreads, your other female plants will start producing seeds instead of high-quality buds.
Even a slight breeze or a fan can carry pollen, so act fast and handle hermies with care.
Takeaways
Preventing hermaphrodite cannabis plants comes down to early detection and stress management.
A stable environment and careful monitoring can save your harvest from unwanted pollination.Key steps to follow:
- Monitor for pollen sacs during pre-flowering and throughout the flowering stage.
- Minimise the stress your plants are under by maintaining consistent light cycles, proper training techniques, and stable temperature and humidity levels.
- Act quickly if you spot a hermie; either remove the plant entirely or carefully remove sacs before they open.
By keeping your grow conditions optimal and responding promptly to signs of stress, you can maintain healthy, potent, and seed-free female plants for the best possible yield.
Happy growing!
FAQs
How to tell if a plant is turning hermaphrodite?
A hermaphrodite cannabis plant develops both male and female reproductive organs, meaning it can self-pollinate and ruin your crop.
The first signs usually appear at the nodes where branches meet the main stem.
Look for small, round pollen sacs forming alongside female flowers; these may appear as tiny "bananas" (nanners) inside the buds.
If you spot both pollen producing sacs and female pistils on the same plant, it’s turning hermie.
Check your plants daily during pre-flowering and early flowering stages.
Catching these signs early can prevent pollination and save your yield.
Are hermie plants worth keeping?
In most cases, hermie plants aren’t worth keeping.
Once a plant has produced pollen sacs, it risks pollinating your female plants, leading to seedy, low-quality buds instead of potent, resinous flowers.
If you catch a hermie early, you can try removing the pollen sacs, but even one missed sac can ruin your entire grow.
For small home grows, removing the plant completely to protect your other plants is usually safer.
However, if you're growing it for seeds rather than flowers, like a male cannabis plant, you might keep it.
Do hermie plants still produce buds?
Yes, hermie plants still produce buds, but they won’t be the high-quality, seedless flowers you want.
Once a hermaphrodite cannabis plant develops pollen sacks, it can self-pollinate, leading to buds filled with seeds instead of dense, potent flower.
These buds will have lower THC content and less flavour and aroma compared to properly cultivated female cannabis plants.
Should I get rid of a hermaphrodite plant?Yes, removing a hermaphrodite plant is usually the best choice.
Once a hermie cannabis plant develops pollen sacs, it can pollinate nearby female plants, leading to seedy, low-quality buds instead of potent, resinous flowers.
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