King Palm Decline: Spider Mites Ruled Out, High pH Identified

A 10-year-old King Palm in San Diego produces new fronds that frizzle within days. Initial suspect: spider mites. Test (rapping fronds over white paper) negative.

Soil Test Reveals Critical Issues

A soil tester showed:

• Overwatering (soil too wet)
• pH 9.5 (extremely alkaline; target ~6.5)

Corrective Plan

1. Reduce watering frequency.
2. Lower pH gradually with organic matter: peat moss, compost, mulch worked into soil sparingly.
3. Consider crystal water-absorbing polymers (like rock salt) mixed into root zone to manage excess moisture.
4. Soil lab analysis recommended due to extreme pH after 10 years.

Outcome

Addressing drainage and pH should revive the palm. The 10-year history at pH 9.5 is unusual—verify test accuracy.

Expert insight provided by Melissa.