Costco is urging customers who recently purchased a certain plant to isolate it immediately after discovering the plants may be infested with an invasive insect capable of spreading diseases that can kill grapevines and damage other crops.
The warning applies to desert willow plants (Item #25215) sold between June 24 and July 3, 2026, according to a notice Costco sent to affected members.
The retailer said the plants may contain the glassy-winged sharpshooter, a large leafhopper that spreads harmful plant diseases.
“This invasive insect pest can spread harmful plant diseases, including Pierce’s disease, which can kill grapevines,” Costco wrote in the notice.
“The pest can also damage citrus trees, landscape plants and other crops. Early detection and rapid response are critical to preventing the pest from spreading further.”
Customers who purchased one of the affected plants are being told to keep it in its original container and away from other plants. Costco also advises customers not to plant, transport, relocate, throw away or compost the plant.
If possible, the company recommends placing the plant inside two sealed trash bags while awaiting instructions from local agricultural officials.
Rather than returning the plant to a warehouse, Costco is asking customers to contact their local county agricultural commissioner’s office so inspectors can examine the plant.
If the insect is found, officials will safely remove and dispose of it and may place monitoring traps nearby.
Customers can receive a full refund by presenting the notification letter at a Costco warehouse. The company specifically asks customers not to bring the plant back to the store.
“We apologize for any inconvenience this has caused and appreciate your attention and cooperation in this matter,” Costco wrote. “Your support helps safeguard California’s agriculture.”
Why the pest is a concern
According to the US Department of Agriculture, the glassy-winged sharpshooter thrives in warm, sunny climates and is one of the most effective insects at spreading Pierce’s disease.
The warning follows another recent detection involving Costco plants. In May, Napa County agricultural officials announced that 63 of 220 grapevines shipped from a Fresno County nursery to a Costco warehouse in Napa County were infested with glassy-winged sharpshooters.
The insect has caused significant agricultural damage in California. A 2008 University of California study found that Pierce’s disease caused nearly $30 million in losses and destroyed more than 1,000 acres of grapevines between 1994 and 2000.
