Jacaranda Dieback in San Diego: Heat, Wind, or Water Stress?

20-Foot Jacaranda Lost Last Year's Growth — Why?

After a healthy bloom last July, your jacaranda showed sparse flowers this June, with 6–12" dieback on all branches and heavy suckering from the trunk. Neighbors' trees similar; one downhill/out of wind is fine.

Top Suspects

• February heat wave (90°F): Extreme heat + low humidity = massive transpiration pull. If soil moisture was marginal, roots couldn't keep up — causing tip dieback.
• Wind desiccation: Your exposed location vs. protected neighbor explains the difference. Wind strips moisture from leaves faster than roots replace it.
• Frost? Unlikely if no freeze recorded, but radiational cooling on clear nights can nip tender tips.

Recovery Plan

• Deep water weekly through dry season — jacarandas have deep roots.
• Mulch heavily to conserve moisture.
• Leave suckers — they're the tree's backup photosynthetic factory.
• Prune dead tips only after new growth hardens.

Prevention

Anticipate heat waves: pre-water deeply before forecasted extremes. Consider a windbreak if this pattern repeats.