Leaf scorch due to direct sunlight during the growing season is often caused by a sudden change in exposure caused by tree removal or transplanting from shady areas into sunny areas. Drought conditions can also cause leaf scorching along the margins or leaf tips.
Also, some plants grow best in partial sun or shade. When shade-loving plants, such as hosta or impatiens, are planted in full sun, leaf scorch or sunburn can occur. Strong sun and heat cause the breakdown of chlorophyll in the leaf. Damage appears as pale, bleached or faded areas. These areas eventually become brown and brittle. Symptoms are more severe when the strong sun is combined with dry soil conditions. To avoid problems caused by excess sunlight, select plants suited to the growing conditions in your yard. Most shade-loving plants will tolerate morning sun, as long as adequate moisture levels are maintained. Avoid planting in locations exposed to strong mid-day sun.
Sunburn may also occur on greenhouse grown plants that are adapted to low light conditions and planted directly outdoors without a "hardening off" period. To avoid sun scorch on greenhouse grown plants, place plants in full sun for 2 hours per day initially and gradually increase the length of sun exposure.
Management on annuals and perennials
To avoid problems caused by excess sunlight, select plants suited to the growing conditions in your yard. Most shade-loving plants will tolerate morning sun, as long as adequate moisture levels are maintained. Avoid planting in locations exposed to strong mid-day sun.
Management on groundcovers
To reduce the chance of winter burn, water well and make sure the soil has adequate moisture during the fall before winter conditions arrive.
Prune, thin or mow damaged plantings in the spring to encourage new growth.
Maintain adequate soil moisture levels to reduce leaf scorch during the growing season.
Sudden changes in sunlight exposure may burn existing foliage.
