The disease does not occur as frequently and may not be as severe on well-drained sandy soils as in heavy clays or poorly drained soils, etc. The disease is common and severe in areas where run-off water, rain water from roofs, etc. collects around plant roots. Shallow soils with underlying rock or compacted hard pans, setting woody plants deeper than the soil level in the nursery or container, over-watering plants, or long periods of heavy rain also favor disease development. Purchase disease-free plants from a reputable nursery. Avoid plants that lack normal green color, appear wilted in the morning, evergreen plants that have excessive winter defoliation or dark discolored roots.
Plant root rot susceptible plants in well drain areas.
If excess water from any source collects in the planting site, avoid planting root rot susceptible plants. The material should be incorporated to a depth of 8-12 inches. In some areas drain tile and gravel placed 6-12 inches below the surface may also help reduce excess soil moisture. Do not set the new plant any deeper than the soil level in the container or the soil line in the nursery. Firm the soil beneath the soil ball so that the plant will not settle into the bed.