The best ways to clean and re-use your PBS pollination bags
We are often asked about the best ways to clean a PBS pollen bag in order that it can be re-used. Depending on the equipment and materials that you have to hand, here are the best methods of sterilising the bags without damaging them.
1. Cleaning: a pollination bag can be cleaned by brushing off loose residues then washing thoroughly in detergent and hot water. They can be oven dried at a temperature of around 105ºC.
2. Heat Sterilizing/Autoclaving: pollen bags can be autoclaved at 121ºC for 15 minutes, although 105ºC is generally considered adequate. At these temperatures, the white polyester material won’t be affected, but some shrinkage to the PVC window may occur. Autoclaving for more than a total of 1½ hours weakens the bags and isn’t recommended.
When the PVC windows cool down they can stick together if in contact with each other. We recommend stacking the bags with windows at opposite ends, or placing a piece of silver foil placed between the layers. Alternatively, you can simply separate bags whilst they’re still warm.
3. Chemical Sterilizing: this is a useful approach because it can remove discolouration on the bag material as well as providing sterilization.
- Sodium Hypochlorite – autoclaved bags which have been soaked in a 10% solution for 20 minutes are both bleached and sterilized.
- Mercuric Chloride – our bags have been tested by soaking in 0.1% mercuric chloride solution for as long as one hour and showed no deterioration.
- After the use of Sodium Hypochlorite or Mercuric Chloride, the bags must be washed in water very thoroughly in order to remove any residues which may be harmful to the plants or material which might be a nutritional supply for fungi.
- Alcohol & Formalin – washed bags can be sprayed with alcohol or 5% formalin solution before oven drying at 105ºC for 12-24 hours.
- Propylene Oxide – brushed, washed and dried bags can be treated with propylene oxide to sterilize.
We think that a major advantage of PBS pollination bags is that they are reusable – meaning that they can deliver fantastic value over several seasons. Tell us what you think by leaving a response on the message board.