Overview

The phlox plant bug, Lopidea davisi, is an eye-catching true bug. It is reddish-orange and black. It is a piercing-sucking insect with a long proboscis. It feeds mainly on phlox and can cause serious damage to phlox.

Symptoms and Diagnosis

The phlox bug’s feeding causes white or light green spots on the leaves and buds that later show yellow stippling. The leaves then turn brown, curl, dry out and drop. The plant may become stunted and die. The bug feeds on leaves, stem terminals, flowers, and seeds. It may be hard to see because it hides on the underside of leaves.

Life Cycle

The phlox bug overwinters in the egg stage in dead phlox stems. It has two generations per year. The first generation appears in late spring, the second in mid to late summer. It undergoes incomplete metamorphosis.

Integrated Pest Management Strategies

1. Practice good sanitation. Cut back and dispose of badly infested stems and leaves. Clean up stem and leaf litter of phlox and neighboring plants in winter before early spring.

2. Scout for nymphs and treat. Apply insecticidal soap to both the upper and underside of the leaves. Use a light horticultural oil.

3. Use chemical controls if warranted. Products listed for use include pyrethrins, permethrin, or acephate (orthene), a systemic.

Organic Strategies

Strategy 1 is a strictly organic approach. For an organic approach to Strategies 2 and 3, consult the Organic Materials Review Institute (OMRI™) for appropriate insecticidal soap and pyrethrin products.

Pesticide Disclaimer: 

Always follow the product's label and ensure the product is effective against phlox bugs. Not following the pesticide label before usage is a violation of federal law.