I am in the process of preparing my garden for the coming season. I topped up the garden with 5 bags of compost. When digging it in I noticed there is a lot of white stuff coming up . Any idea what this might be and is it harmful. Thanks.

Hi Phil, the white substance is not harmful to humans or plants and is beneficial to the soil. The white substance is beneficial soil fungi called mycorrhiza which breaks down the organic matter in the compost (and soil) releasing nutrients into the soil which plants can then take up. The white fungi disappear over time once exposed to air and moisture. Always use caution when handling, using or making your own growing media, store bought or home made compost and garden soil as it can contain a bacteria that causes Legionnaires disease. Legionnaires disease has flu-like symptoms that is treated with high dose antibiotics, for healthy people it isn’t usually a concern, but for those with a compromised immune system, susceptible to respiratory disease, lung or heart disease, or recovering from surgery or an illness then extra care must be taken, wear gloves, a mask and open bags in a well-ventilated area with good air circulation.