expected or desired circumference defined by the drip line of the plant 26 the conventional definition of a drip line of a plant is the perimeter defined by the vertical protection onto the ground of the outermost branches on the plant thus it will be appreciated that the device 10 may be made in several convenient sizes to accommodate the size of common landscaping or gardening plants the device 10 may be utilized either when the plant is first buried in the ground or may be inserted at a later date into the soil after the plant has been established once one or more of the problems discussed have been identified since the device will be made of a stiff material such as 1 4 inch thickness plastic it may simply be inserted into the soil using the leading lower edge of the sheath 14 and driving the sheath 14 into the soil in any convenient manner leaving the lip 18 above the soil the second interlocking member 12b may then be similarly inserted and simultaneously interlocked with the first inserted piece 12a once inserted the lip 18 forms a berm surrounding the base of the plant 26 above ground to collect overhead water and retain it within the drip line of the plant in most instances the drip line of the plant also defines the outer underground extent of the root system 16 therefore the berm allows for efficient watering of the plant where it most needs the water directly above its root system furthermore the sheath 14 forms an annular.