I have a white, fibrous, mildewy substance under the mulch in one of the areas I'm planting in this spring. I removed all of the mulch today and most of the top layer of soil. My question is... could the mildew still be hanging out in the soil and potentially harm new plantings?? We plan on tilling and heavily amending this area before planting time, but I'm worried that the mildew will multiply and wreak havoc. The site is full sun.
I'm wondering if the mulch didn't have mildew in it when the builders laid it down??? They basically tried to create a shrub bed by laying 6" of topsoil over compacted clay and mulching like crazy. The mildew was between the mulch and topsoil layers.
Any thoughts??? I'd hate to plant new plantings in this area only to loose them from mildew damage. Thanks :)
P.S. Should also mention that we plan on using Round-up 2 weeks before planting time to eradicate any weeds...