WSU Extension

Hortsense

Caption: Thrips damage on basil
Photo by: A.L. Antonelli
  
print version| pdf version| email url    

Rose : Thrips
(revision date: 3/10/2017)


Biology
Thrips are tiny yellowish to dark insects that feed in flower and leaf buds. Damaged leaves may be distorted, while infested flower buds may be distorted if they open. Heavily infested flower buds may fail to open. Infested flowers have brown spots on the petals. Thrips on roses are mainly an aesthetic concern.
Management Options

Non-Chemical Management
  • Encourage natural predators such as ladybird beetle larvae and lacewing larvae which help control thrips populations.
  • Remove debris from around plants in fall to reduce numbers of overwintering adults.
Select non-chemical management options as your first choice!

Chemical Management


Thrips are difficult to control. Make spray applications directly into the flower bud or flower. Follow label instructions for products applied as a drench. Test a bud or flower to see if the chemical can be tolerated.

Listed below are examples of pesticides that are legal in Washington. Always read and follow all label directions.
  • Bonide Captain Jack's Deadbug Brew R-T-U [Organic]
    Active ingredient: spinosad (spinosyn A+D)  |  EPA reg no: 4-472
  • Monterey Garden Insect Spray [Organic]
    Active ingredient: spinosad (spinosyn A+D)  |  EPA reg no: 62719-314-54705
  • Naturalis L
    Active ingredient: Beauveria bassiana  |  EPA reg no: 53871-9
  • This list may not include all products registered for this use.
Images
    - hide images

+ Show larger images

 
Caption: Thrips damage on basil
Photo by: A.L. Antonelli
Caption: Thrips damage on pea
Photo by: A.L. Antonelli
Caption: Thrips
Photo by: Unknown