I had a prunus tree die from honey fungus infection which then started to spread to conifers within the bed. The bed was isolated from the rest of the garden by a tarmac driveway, so I'd planned to sterilise the bed sometime in the future.

However, last year I decided to throw all of the mulched laurel hedge cuttings on to the bed everytime i cut the hedge.

In the Autumn, there was suprisingly no fungus growth and having inspected the soil, the honey fungus seems to have gone!

Could it be the cyanide that mulched laurel leaves give off when they are crushed?