Small Silver Bugs in the Soil of Orchid Plants

Healthy orchid blooms

Orchids are garden and house plants widely grown for their exquisite flowers and often intricately patterned foliage. Some orchids, given the proper care, will bloom repeatedly. Silver or gray bugs in the soil around your orchid indicate a problem.

Types of Pests

The Bois du Val soft scale -- a tiny, pale gray insect -- infests all parts of an orchid from its roots to its buds. Large numbers of the pest may surface as a solid covering on parts of the plant. Grayish-pink orchid mealybugs (Pseudococcus dendrobiorum) secrete a white waxy substance that helps conceal their infestations among an orchid's roots. These insects infest cymbidium, phalaenopsis, pholidota, promatocalpum and ascoglossum orchid species. Scales and mealybugs feed on orchid tissue fluids.

Scale Control

Dissolve soap shavings in warm water and thoroughly wash your orchid with the soapy solution. Repeat every other day for a month. Observe the orchid for reinfestations for another month, while separating it from other plants.

Mealy Bug Control

Dispose of severely infected orchids. Remove light mealy bug infestations with an alcohol-saturated swab. Wash the plant with a cloth or brush dipped into a solution of 2 tsp. of liquid dish detergent in 1 gallon of warm water.

References

• Canadian Orchid Congress: Scale Insects on Orchids; Ingrid Schmidt-Ostrander
• Florida Department of Agriculture & Consumer Services Pest Alert: Orchid Mealybug, Pseudococcus Dendrobiorum Williams (Hemiptera: Pseudococcidae); Greg Hodges et al; April 2009
• Cornell University Insect Diagnostic Laboratory: Mealybugs on Houseplants; Carolyn Klass; June 2005

Resources

• UT Extension: Growing Orchids in the Home; Linda M. Seals et al.