Crown Rot

Crown Rot may sound like a great punk rock band, but it can destroy many plants in the garden.

---

Crown Rot is caused by a soil fungus that is nearly guaranteed to kill a plant once infestation occurs. It favors heavy clay soils and wet conditions that occur with over-watering and flooding that comes in January and February, in the Bay Area.

Photo of crown rot on sugar beets from NDSU

---

Crown rot symptoms

Signs of crown rot include rotted plant tissue at ground level, wilting, leaf drop, trunk discoloration and leaves that turn yellow or even red or purple. Established trees may ooze a dark sap around the infected area. Older plants may survive a few years, but young plants normally die quickly.


If crown rot is found in the garden, your best choice is to pull up the plant and discard it. In rare cases, a tree can be saved by pulling soil away from the trunk and cutting away diseased areas. Fungicides are ineffective in treating Crown Rot.


Preventing crown rot

Prevention is the best course of action in areas prone to crown rot. To reduce the likelihood of crown rot taking hold, use these preventative measures:

• Ensure proper drainage 
• Amend soil with organic matter and compost
• Plant trees properly, with grafting unions above ground  level
• Keep mulch at least 6” away from trunks
• Never allow sprinklers to spray tree trunks
• Rotate crops such as tomatoes each year