E-mail - Preventing Unwanted Seeds or Pollen Protection

Dear Doctor Myers,
I'm having a horrible time with my plants going to seed. My flowering room and vegetation room are separate. I don't know when or where the pollen has come from and I really don't know what to do. I will have the flower room empty very soon and can clean the room but it's lined with Mylar. How do I clean the pollen out of the whole grow room?

  Thanks for your question.  There are many reasons to prevent seeds first would be to ensure a true breeding line. To do this you will need to make sure there is no pollen (plant equivalent to sperm) in the room where you are inducing flowering. The easiest way to do this is to remove the male part of the flower (plant sex link), or male flowers or male plants, depending on the species of plant you grow. If you grow plants that have a perfect flower (male and female in same flower - like peas) you will have to remove the male part from every flower. If you have both male and female flowers on the same plant you can remove the male flowers but both of these situations you will have a hard time not getting seeds if you are not consistently and accurately checking your plants.. If you grow plants that are male and female (separate sexes) you can remove the entire male plant. A problem with plants that have separate male and female plants is that you may have a plant that is a hermaphrodite (has both flowers usually a small number of male flowers on an otherwise female plant), these hermaphrodites can be due to genetics or stress from high heat, or light getting in during the dark cycle, or poor nutrients (check for these problems in your garden as all can cause hermaphrodites)... If you think you have hermaphrodite plants, you may want to start over with different seeds to be safe.

Pollen from some plants can float in the air for days. You need to wipe down the Mylar and all surfaces in the room with a cleaner that has ammonia to kill any pollen. High temperatures and moisture can also kill pollen, so after you wipe down the room, try to have very high temperatures if you can for a couple days (leave light on with out exhaust fan for example). And spray the room with a water bottle once a day. Pollen usually is only viable for a couple days at warm temperatures.
I have written about pollination in previous posts

A carbon filter  might help cut down on pollen production, but it could also blow pollen around the grow room and make your problem worse if you have the air blowing across your plants like I have recommended in order to increase airflow and the growth rate. However, If you vent the carbon filter air outside the grow room, preferably outside the building, that might cut down on pollen.
Good Growing,
Dr. E.R. Myers