My Ornamental Plant Is Turning Brown

A number of factors may cause ornamental leaves to turn brown.

An ornamental plant with brown leaves is not an unusual sight. A number of ornamentals have leaves that will turn pale yellow or brown before dropping. This is part of the normal growing process and will usually affect lower leaves. In some cases, however, leaves turning brown are an early indication of health problems normally associated with fungal or bacterial diseases and a few environmental factors. The sooner the problem is addressed, the more likely it is the plant will make a full recovery. Does this Spark an idea?

Light

If the leaves on an ornamental begin turning brown, it may be an indication of too little sunlight exposure. If this is the cause, the discoloring will occur on the side furthest from the light source. Different plant types require a varying amount of sunlight to thrive. It is important to carefully monitor sun exposure in all plants. Too much and too little may cause problems with leaf browning. Some plants, including the peace lily, may even require filtered or indirect sunlight. Following these exposure recommendations will assure the best growth and overall health of the plant.

Heat and Water

Typically, heat is a problem to plants that becomes worse when water is scarce. If these conditions are not corrected, it is likely that leaves will start to wither and droop. If high temperatures continue and watering is infrequent or inadequate, the leaves will normally turn brown before dropping. This problem is generally an easy one to fix and should be corrected as soon as possible. Outdoor plants should be watered more frequently during the summer, and most types should be given an area with at least partial shade. Indoor plants may suffer leaf browning if soil isn't draining properly. If the soil holds too much or drains too quickly, nutrition may be lost and affect growth and leaf color.

Root Rot

Root rot is a fungal disease that will first infect the plant through feeder roots. It infects a large number of plant breeds, including several ornamentals, and is often fatal. The fungus that causes the disease is found in the soil, and will thrive in favorable conditions, including soils that drain improperly. Infected roots will turn into a mushy gray substance, which will progress until leaves turn yellow or brown and begin to drop. Early symptoms of the disease include reduced growth, leaf wilt and premature leaf dropping. Early treatment is the key, and preventative measures are ideal. Pasteurized soil is ideal, loam-type soil to provide drainage and proper sun is the best to prevent overgrowth of fungi.

Cercospora Leaf Spot

Cercospora leaf spot is a bacterial infection that can affect a number of ornamental plants. The bacteria will begin in the stem and move through the plant to the leaves. The illness will show up as dark green or brown spots that will eventually kill and cause the leaves to drop. The bacterium may be found in soil and will thrive in overwatered or poorly drained soil. Like other fungal infections, it will start in the roots and make its way up the plant. It is best treated in the early stages with a copper-based fungicide.

References

• The Garden Helper: Plant Health Problems
• University of Minnesota Extension; Root Rot of Houseplants; Jill Pokorny; February 2000
• University of California Davis: Sugarbeet Pest Management Evaluation Cercospora Leaf Spot

Resources

• Conn. Agricultural Experiment Station; Recognizing Tree Diseases ...; Sharon Douglas; Dec. 1997
• Washington State University; Watering Home Gardens ...; George J. Pinyuh, et al.
• Gardening Know How: What Causes Brown Edges on Leaves of Plant