Tips for Yellowing Leaves on a Yucca Plant

Watering Practices

• Over- or underwatering a yucca plant causes the foliage to turn yellow, wilt or shrivel up. Although naturally accustomed to arid conditions, following an irregular or erratic irrigation schedule in the summer dehydrates the roots, causing the foliage to discolor. On the other hand, overwatering the plant prevents oxygen absorption, thereby causing the foliage to turn yellow and then black. If the soil around the yucca appears dry and cracked, water deeply until it is evenly moist, and irrigate every day for the next few days to hydrate the plant. Conversely, hold back watering if the leaves turned yellow after a recent irrigation practice. Ideally, allow the top 2 inches of soil to dry between watering.

Sunlight Exposure

• Provide yucca full sunlight so it remains healthy and retains its natural color. Move the potted yucca to a spot exposed to six hours of sunlight every day, or cut back overhanging branches of surrounding trees to increase sunlight penetration for ground-planted yuccas. Maintain consistent temperatures between 70 and 80 degrees Fahrenheit during the day, and 10 degrees lesser during the night. Avoid sudden changes in temperature that cause foliage discoloration.

Root Rot

• Root problems increase plant stress that manifest themselves as yellowing foliage, along with other symptoms. Root rot, a condition caused by overwatering the roots or causing them to stand in pools of water for prolonged periods, damages the roots, causing them to turn brown and slimy. Pot-bound yucca roots begin crowding due to lack of space. Repot your yucca plant to a larger pot if the foliage discoloration is accompanied with other symptoms such as the presence of roots along the top of the soil or the tips of roots emerging from drainage holes.

Other Care Tips

• Inspect your garden or container yucca regularly for symptoms related to yellowing foliage, so you take necessary steps to help the plant regain its natural vigor. Yellowing foliage is also caused due to sucking pests such as aphids, scales and thrips that sap essential juices from the leaves, causing them to wilt and turn yellow. Treat pest infestations with horticultural oils or a mild insecticide. Rectify yellow leaf spots that indicate a fungal disease with a registered fungicide before they join to form larger patches that cover the entire surface.