Diagnosing and Treating a Declining Ligustrum Tree

A mature ligustrum (privet) showing light green, curled, dried leaves on one side—especially the south-facing side—signals stress. While root rot is possible, other factors like fungal infection, nutrient imbalance, or environmental stress are more likely in a long-established tree.

Potential Causes

• Fungal disease spreading from one side (often due to uneven moisture or sun exposure).
• Over-fertilization causing metabolic imbalance and root damage.
• Root issues from poor drainage, compaction, or nearby construction.

Diagnostic Steps

1. Check soil moisture and drainage around the root zone.
2. Inspect the trunk base for bark damage, fungal conks, or insect activity.
3. Take a soil sample for nutrient and pH testing via your local extension service.
4. Consider a certified arborist for an on-site evaluation, especially for a valuable specimen.

Treatment Approach

Foliar sprays with a broad-spectrum fungicide or plant health promoter (like compost tea or seaweed extract) may help if caught early. Address underlying causes: correct drainage, adjust fertilization, and mulch properly (keep mulch away from trunk). Nearby ligustrums should be monitored but not treated prophylactically without evidence of spread.