Daylily: Thrips
categories: Bulbs Daylily Daylily Insects Ornamentals
revision date: 2023-02-07 12:00
Photo by: R.S. Byther
Biology
Several species of thrips may be found on daylilies. Thrips are tiny (usually less than 1⁄8 inch long), fast-moving insects often found on leaves and between flower petals. Adults are typically yellow to brown; nymphs are usually yellow to whitish. Both immature nymphs and adults may feed on leaves and flower buds. A common symptom of thrips feeding damage is the presence of silvery streaks or speckles on leaf and flower tissues. Typical thrips damage is primarily cosmetic, but stressed plants or hot, dry weather conditions can result in more serious damage. Heavy infestations may cause leaf and flower stunting and distortion, and buds may die and drop from the plant without opening. Because of this, damage caused by thrips may be confused with that caused by daylily gall midge larvae. However, gall midge larvae are both legless and wingless and feed exclusively inside flower buds.
Management Options
Use Integrated Pest Management (IPM) for successful plant problem management.
Non-chemical Management
Select non-chemical management options as your first choice!
- Provide proper nutrition and soil moisture. Excess nitrogen and dry conditions make daylilies more susceptible to thrips damage.
- Natural enemies including predaceous thrips help control populations of plant-feeding thrips. Avoid use of broad-spectrum insecticides to conserve these beneficial insects.
- Sprinkler irrigation or heavy rain may help control thrips populations.
- Control weeds in and around the garden.
Chemical Management
IMPORTANT: Visit Home and Garden Fact Sheets for more information on using pesticides.
Apply products before bloom, when thrips are first seen. Do not apply after plants are in bloom, as these products are toxic to bees.
Approved Pesticides
Listed below are examples of pesticides that are legal in Washington. Always read and follow all label directions.