Hello Professor Lee,
I am terrified of hermaphrodite plants! My first crop was heavily seeded by just a few male flowers on otherwise female plants. I’m not sure if it was something I did or if the plants I grew were naturally hermies. I want to spend my time growing buds not seeds. What can I do to prevent this in the future?
Many a fine crop has been ruined by hermaphrodite plants. The worst case I saw involved a good friend of mine who grew in his bedroom closet. He had a bad habit of leaving the door open while he read at night. The result was a huge harvest of seeds and some scrawny buds.
Environmental factors that can create hermaphrodite plants include things like the above-mentioned light pollution, inconsistent light cycles, plant stress (such as nutrient burn or heat stress) and temperature problems. It’s best to keep the garden about 10°F to 20°F (6°C-9°C) degrees cooler at night. Never let the grow room temperature get above 85°F (29.4°C) during the day.
Of course, genetics do come into play. Some strains are just naturally prone to producing hermaphrodite flowers. When possible, always use seeds from reputable companies. Breeders should avoid using hermaphrodite plants in their breeding programs as this undesirable trait can be passed along to future generations.
The best time to look for hermaphrodite flowers starts when the plants are about 4-6 weeks old. Female pre-flowers will begin to send up the familiar white pistils, while male pre-flowers resemble a banana with two sacs underneath. After removing any obvious male plants, give the remaining females a closer examination. Any plants with both male and female flowers should also be removed. Some hermaphrodite plants will only produce the odd male flower, but other will continue to develop more and more as they develop. It’s better to have a lighter harvest of ripe sinsemilla than scrawny seed-laden buds.
Before you start another crop, clean your garden and sit in it with the lights turned off. Look for any light leaks. If you find any, fix them before introducing new plants. Also, consider the source of your seeds and the temperature fluctuations that occur in your garden. Chances are it’s one of these that led to your problem.