Lenten rose is a flowering perennial small shrub that is a known botanically as Helleborus orientalis. While not related to the rose, its flower resembles a single rose flower and blooms in early spring around Lent, hence the name. Lenten rose grows well in moist soil but experiences root rot in overly wet soils or soils with poor water movement and drainage. Root rot can also occur in instances of drought, which causes stress to the plant and roots.
Evaluate the moisture content of the soil by touch testing. Feel the surface of the soil at 3 inches and 10 inches down. Ensure that the soil is evenly moist but not soaking wet. Water dry soil immediately until drenched to a depth of 8 inches or so to alleviate drought stress. Refrain from watering soil that is soaking wet. Wait until it dries out--to the point that it is dry to the touch a few inches below the surface. Apply water around the roots but at least 6 inches away from the central stems so as not to exacerbate rot conditions.
Transplant Lenten roses growing in heavy, poorly drained soils and suffering from root rot. Lift them from the soil, cutting any slimy rotting root material and relocating the plants into fresh, healthy soil. Choose a site with free-draining soil or in a raised bed, a large container with ample drainage or on a slope grade to prevent root rot from recurring and eventually killing the plant.
Alter the existing soil around your Lenten rose by aerating and amending the soil vertically. Excavate 2-inch diameter holes roughly 18 inches deep every 12 inches surrounding the plant in a ring along the drip line. Fill the holes to the top with equal parts fine gravel or sharp sand and peat moss or perlite to improve drainage.