Sunburn

You might be surprised to learn that your plants can get sunburned this 4th of July, just the way you can. Okay, so maybe it’s a little different, but too much sun can be deadly in either case. 

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Plants certainly need sunlight for photosynthesis, but too much of a good thing can be a bad thing. Sunburn damages plant tissue and provides an entry point for pests and disease.


When leaves first get too much sun, chlorosis (yellowing) occurs. Serious sunburn causes irreparable browned areas, usually between the veins.

Photos of sunburn and sun scald damage from UC IPM

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When bark gets too much sun it is called sun scald and it can kill a tree. The damaged bark blisters and cracks, exposing internal tissue to pests and disease. To prevent sun scald, exposed branches and trunks can be painted with a 1:1 dilution of water and white latex paint. Do not use enamel paint because the tree needs to breath.


Selecting the right plant varieties and choosing the proper location are good ways to avoid sunburn and sun scald. Plants that are watered properly are less likely to be sunburned. 


Be sure to water your plants thoroughly this summer (and especially on July 4th) to help protect against sunburn, sun scald, and bottle rockets.