African Violets are cherished houseplants, known for their beautiful flowers. Brown leaves are a common concern, indicating various underlying issues. Understanding these causes is the first step toward restoring your plant’s health. This guide identifies why your African Violet’s leaves turn brown and how to address these problems.
Common Causes and Solutions for Brown Leaves
Watering Problems
Incorrect watering often causes brown leaves on African Violets. Overwatering leads to dark, mushy brown leaves, especially at the base, due to root rot from saturated soil. If the soil is consistently soggy, leaves become limp and brown. To remedy this, stop watering and allow the soil to dry out significantly.
Underwatering results in dry, crispy brown edges or entire leaves, indicating severe dehydration. Leaves may shrivel and feel brittle. If the soil is bone dry, the plant needs water. To revive it, water thoroughly from the bottom by placing the pot in a saucer of room-temperature water for 15 to 30 minutes, allowing absorption through drainage holes.
Light Issues
Inappropriate light conditions can also cause brown leaves. Too much direct sunlight leads to scorched, bleached, or crispy brown spots, burning the delicate foliage. If your plant is in a sunny spot, move it to an area with filtered light or use sheer curtains.
Insufficient light can stress the plant, leading to pale leaves or browning edges. Leaves may also appear thin, deep green, and the plant might become leggy. African Violets thrive in bright, indirect light, mimicking their natural habitat where sunlight is filtered.
Humidity and Temperature
Low humidity can cause African Violet leaf edges to become crispy and brown. These plants prefer relative humidity between 40% and 70%, ideally 60-80%. Sudden temperature fluctuations or cold drafts can also lead to brown patches, wilting, or brittle leaves. African Violets prefer consistent temperatures between 65°F and 80°F, with 70°F being optimal.
To address low humidity, place the plant on a pebble tray filled with water, ensuring the pot does not sit directly in it. If cold drafts are the issue, move the plant away from windows, vents, or frequently opened doors. If exposed to cold, move the plant to a warmer spot and remove any dark, mushy tissue to prevent rot.
Nutrient Imbalance
Both over-fertilization and nutrient deficiencies can cause browning. Over-fertilization results in burnt, crispy brown edges and salt buildup in the soil, which can burn roots. Orange or yellow crystals may appear on the soil surface or pot rim. To correct this, gently flush the soil with room-temperature water, allowing complete drainage, then withhold fertilizer for a month.
Nutrient deficiencies, while less common for direct browning, can make leaves susceptible to problems. For instance, potassium deficiency can lead to leaves yellowing and browning at the tips. Nitrogen deficiency often presents as yellowing leaves and stunted growth, particularly in older leaves. A balanced fertilizer can address these deficiencies.
Water Quality
Water quality significantly impacts African Violets, leading to brown spots or rings on leaves. Water that is too cold can cause permanent leaf spotting, appearing as brown blotches or rings where water touches the foliage. Hard water or water with high mineral content, including chlorine or chloramines, can also cause browning or burning.
To mitigate these issues, always use room-temperature water. Allowing tap water to sit uncovered overnight helps chlorine dissipate. Spring water, distilled water, or rainwater can also be beneficial, especially if tap water contains high levels of minerals or chloramines. When watering, avoid splashing water onto the leaves.
Pests and Diseases
Pests and diseases can contribute to brown leaves. Spider mites or thrips can cause leaf discoloration and damage, appearing as small brown flecks or browning with webbing. Fungal diseases like crown rot or Botrytis blight can cause leaves to turn brown and mushy, or develop fuzzy gray and brown spots, especially in overly wet or humid conditions.
Regular inspection helps catch infestations or infections early. For pests, an insecticidal soap spray is an effective treatment. For fungal issues, improve air circulation and avoid wet foliage. Severe rot may require discarding the affected plant to prevent spread.
Preventative Care for African Violets
Preventing brown leaves requires consistent, proactive care. Implement proper watering techniques, allowing the top half inch of soil to dry before bottom-watering to prevent crown saturation. Provide bright, indirect light; if natural light is insufficient, use fluorescent or LED grow lights positioned 8-12 inches above plants for 12-14 hours daily.
Maintain consistent temperatures between 65-80°F and humidity above 50%, utilizing humidity trays or a room humidifier as needed. Fertilize regularly with a balanced, water-soluble African Violet fertilizer (e.g., 20-20-20 NPK), diluted to half or quarter strength, every 2-3 weeks during active growth. Additionally, use a specialized, light, and well-draining African Violet potting mix to promote healthy root development and prevent waterlogging.
Removing Affected Leaves
Once the cause of brown leaves is addressed, removing affected foliage is beneficial. This improves the plant’s appearance and redirects energy toward new, healthy growth. It can also prevent the spread of potential diseases or pests localized to the damaged leaf.
To remove a brown or damaged leaf, use clean, sharp scissors or a sterile knife. Make a clean cut as close to the main stem as possible, without damaging surrounding healthy tissue. Removing older, browning outer leaves is a normal part of African Violet grooming, as new leaves grow from the inside out. Regular removal of spent flowers and discolored leaves encourages new blooms and maintains vigor.