How to clean and sterilise poly hives
How to clean and especially sterilise poly hives has been a major issue in the UK for a number of years, but the National Bee Unit (NBU) now produce a leaflet on hive cleaning which gives recommendation for poly hives. The leaflet is called "Hive Cleaning and Sterilisation" and can be downloaded from the NBU website.
After scraping, a chemical treatment is then generally used for final cleaning.
The NBU recommendations are for the use of washing soda for general cleaning. Washing soda is obtainable from hardware shops and some supermarkets and should be diluted as directed on the packet. A large bucket is essential for cleaning and these can be bought from DIY and Builders' suppliers. Alternatively, but more expensive, a Plasterers Bucket is a larger container which can be obtained from specialist suppliers.
Before cleaning poly hives, which is best done outside, put on a good waterproof apron, elbow length rubber gloves and protective goggles. Although not totally necessary for the use of washing soda alone, they are strongly recommended and can usually all be bought at a farm supply shop.
Warm water will make the solution work more effectively, loosening propolis and cleaning both the exterior and interior of the hive components. For those used to wooden hives, it will come as a slight surprise to find how buoyant poly hive components are. The components will need to be pressed down into the cleaning solution while they are rubbed with a cloth. A brush can be used but this carries an increased danger of getting the solution into your eyes.
Afterwards the components should be left to drain and then rinsed with cold water. Do not use a power hose - it will damage the surface - a rose type sprinkler is best.
The NBU leaflets recommends the sterilisation of poly hives is carried out with a strong solution of household bleach. For this treatment the protective equipment mentioned above is essential. If AFB or EFB are suspected the local bee inspector should be contacted and their advice followed.
Although the NBU does not recommend the use of other chemical sterilants, the use of Caustic Soda is very well established in European countries, where poly hives have been in long use. In Europe it is commonly called "lye" and it is also an exceptionally effective hive cleaner. A warm caustic soda solution will strip off propolis - and any paint covering as well if it is left in too long! However, caustic soda, especially a warm solution, is highly corrosive and even if used in the open air the use of a full face mask is very strongly recommended, as the fumes rising from the bucket will irritate the skin, especially the sensitive skin of the face.