Help with hermies

I have been growing intermittently for the past seven years. I have had a small percentage of hermaphrodites in nearly every crop. I have been told that it is due to the plants’ environmental conditions, too much nitrogen, or breaking the light cycle, which I didn’t do. Clones from mothers that I grew invariably had male flowers pop right out in the middle of beautiful nugs.
Why are my plants hermaphroditic and what can I do about it?

Phat Phlowers,
Vancouver Island, British Columbia

From your description of the garden it doesn’t seem that your plants are particularly stressed, which often causes some hermaphroditism. Instead, your plants likely have hermaphroditic tendencies as a result of their genetic programming. The variety you are growing probably carries a gene for hermaphroditism. Not all the plants in your garden carry the genes since most of them are not hermaphrodites.

The characteristic could be controlled by a recessive gene. Recessive genes are difficult to identify because the characteristic only appears when both recessive alleles are present. Many plants may carry one recessive gene paired with a dominant gene, so the hermaphroditism characteristic doesn’t appear.

Your letter didn’t mention when the male flowers appear. If they appear at the end of flowering, as the buds are ripening and about to be harvested, they pose no danger and can be taken as indicators of ripening. Many Indica varieties produce these flowers. If they produce pollen, the upside is that it can be used to pollinate younger, fertile female flowers. The resulting seeds will all be female.

Male flowers that appear earlier in the flowering cycle are a more serious threat to unpollinated female flowers. A single male flower releases hundreds of thousands of pollen grains that float in the air and are attracted to the female flowers’ pistils. Thus a single open male flower in a space with even gentle airflow can result in more seeds than you wish to count. For this reason all early or midseason hermaphrodite plants should be removed from the space as soon as they indicate. They are an inherent danger to your crop and should face the zero tolerance policy.

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