What you need to know about hermaphrodite cannabis plants
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Some cannabis plants can produce both male and female organs. Find out how this can be a problem for growers and what to do about it.
Some weed plants display both male and female sexual organs, making them hermaphrodite plants. Although some plants are distinctly male or female, with male plants producing only pollen sacks and female plants only producing pistils and buds, several genetic and environmental factors can churn out a hermaphrodite plant that produces both.
Hermaphrodite genes are not exactly sought after by growers, for the same reasons that it is not desirable to have a male plant present in the grow space when cultivating with the intention to produce massive yields and resinous flowers.
If the pollen sacks go unseen, they will burst, fertilize nearby flowers and cause them to divert energy into seed production rather than continuing to form trichome mass on the buds.
Some strains are genetically inclined to have a very high percentage of hermaphrodite plants, such as Thai sativas, and should be either carefully monitored or avoided. This type of mixed gender plant is known as a "true hermaphrodite". The cause is thoroughly genetic, taking clones from a hermaphrodite mother will most likely produce plants with the same traits as they are highly inheritable.
It is advised to remove hermaphrodite plants from the growing space once identified to prevent them from fertilizing neighbouring plants, preventing them from reaching sensimilla status and lowering their quality with seed production.
It is a possibility to monitor plants extremely carefully and cut the pollen sacks before they split, but this task requires extra effort and still imposes significant risk to the rest of the female crop.
Another type of hermaphroditism that is thought to be brought about by stress produces bisexual flowers on a female plant, although genetics may play a minor role.
When a female plant detects the threat of certain stress-inducing factors in the growing environment during flowering, it can start to produce pollen emitting stamens along side pistils on the flowers themselves, instead at completely different internodes as is the case with a true hermaphrodite. It does this to shorten the flowering period, increasing the chances of passing on its genes.
The pollen sacks of bisexual flowers are different in appearance to those on a true hermaphrodite. They sport a yellow and elongated look and for this reason are often named "bananas". Bananas are actually the exposed sexual organ, known as the stamen, that usually reside inside of pollen sacs. Due to this fact there is no time required for them to mature, burst open and start pollinating. Pollen distribution starts immediately.
For this reason it is best to remove the plant from the growing area immediately and either harvest it, or move it under new lights and see it through to seed. Bananas occur as an attempt of self-pollinating, when a female is late into flowering and has still not received any external pollen to bring her to seed.
Some causes of stress that may instigate this sexual change are:
- Changes in the photoperiod during flowering
- Poor environmental conditions such as temperatures that are too high
- Physical stress such as pruning during the flowering stage
- Infestations of mites and insects
- Incorrect fertilization
To avoid exposing your plants to the many different kinds of physical stress, ensure that topping, pruning, staking and other invasive techniques are completed in the vegetative phase, before the plant starts to flower and becomes more susceptible to sexual change.
Other factors to consider to minimize risk are:
- Always ensure that your lights are an adequate distance from your plants to avoid possible stress in this area.
- Maintain a comfortable temperature for your weed plants during the flowering period, between around 18-30 degrees Celsius/65-85 degrees Fahrenheit.
- Be consistent with lighting during the flowering stage to minimize disturbances that might trigger stress. Check timers, plugs etc.
- Obtain seeds from trusted suppliers to ensure good quality genetics.