There is no single or definitive answer to how Box Blight is transmitted, but the following all play their part:
1. WATER (splash) dispersal is generally cited as the main way Box Blight is transmitted. With the disease cocooned in water droplets, heavy rain can carry the spores from one garden to the next. Similarly, watering (especially overhead watering – an absolute no-no) can also move the spores over a shorter distance
2. The WIND offers some protection to plants in windy locations as it will, of course, blow spores away – but those spores can then come to rest in more sheltered locations. Spores carried on the wind, though, do not cover large distances
3. The spores of Box Blight are sticky and readily attach themselves to just about anything with which they come into contact including BIRDS, ANIMALS and GARDENERS. Our boots, clothing and tools are Box Blight magnets and should be thoroughly cleaned after we have come into contact with Box
4. INFECTED SOIL – remember that the mycelium of Box Blight can easily survive on fallen leaves for up to 6 years and will produce spores as soon as conditions are right – but only if infected plant material has not been scrupulously removed
5. INTRODUCING new Box plants without taking proper precautions – only buy from a reputable source and quarantine for at least six weeks
6. VISITORS – owners and managers of public gardens have cited their visitors as a possible source of infection. Certainly, if you are welcoming hundreds, if not thousands, of strangers into your garden, the chance of one of them being an inadvertent Trojan Horse for Box Blight cannot be ignored. The chance is greatly reduced for the average private garden – but it’s worth checking with your friends and family whether or not they have Box in their garden before you let them near those in yours. They won’t be offended!