Leaf Scorch

Leaf scorch manifests as darkening and drying of leaf margins and tips, often taking on a scorched appearance despite adequate soil moisture. You might see purple or brown spots initially that merge into larger burned areas, making foliage look sun-damaged or heat-stressed. Severely affected leaves may curl, wilt, and drop prematurely. In Western Washington, this is most visible on newly planted trees during establishment, on plants growing near reflective surfaces like paved areas, and on those under water stress during our dry summers. Maples, oaks, dogwoods, and rhododendrons are especially susceptible.

Leaf scorch occurs when water demand exceeds the plant's ability to deliver moisture to leaf margins, often from a combination of factors: drought stress, poor root establishment (particularly common in newly transplanted trees), excessive salt from over-fertilization, or vascular damage from cankers. The damage is cosmetic once it appears, but it signals underlying stress your plant needs addressing. Prevention is your only recourse: water deeply and infrequently during establishment to encourage deep rooting; plant in fall or spring when water is plentiful; improve drainage if soggy soil is the issue; shelter susceptible plants from drying winds; use appropriate fertilizer rates; and avoid planting close to buildings or paved surfaces that radiate heat.