Gallery of Greenhouse Pests and Diseases

A pictorial guide to insects and diseases recently plaguing greenhouse and outdoor floral crops.

For more information on how to prevent problems, scout for these and other pests and manage infestations, see Integrated Pest Management for Bedding Plants, especially the arthropod pests and contagious disease sections.

Pictures and text by Margery Daughtrey and Dan Gilrein, Long Island Horticultural Research and Extension Center, and John Sanderson, Cornell University Department of Entomology.

Alstroemeria - INSV (impatiens necrotic spot virus)
Assorted hosts - thrips feeding injury
Aster - lacebug injury
Azalea - broad mite injury
Basil - Downy Mildew
Chrysanthemum - chrysanthemum white rust
Chrysanthemum - Fusarium stem rot
Chrysanthemum - injury at stem base due to celery leaf tier
Chrysanthemum - leaf miner
Cineraria - new rust disease
Coleus - Downy Mildew on a garden coleus
Coleus - Downy Mildew flecks on foliage
Coleus - Downy Mildew conidia
Coleus - Downy Mildew on 'Red Velvet' cultivar
Coleus - Downy Mildew
Coleus - Downy Mildew
Coleus - Downy Mildew
Coleus - Downy Mildew causing foliage "twisting"
Coleus - Downy Mildew causing leaf drop
Coleus - Downy Mildew on a seed-grown coleus
Coleus - Downy Mildew causing leaf curling and dead leaf patches
Garden mum - closeup of Rhizoctonia on leaves
Garden mum - Rhizoctonia foliar blight
Hosta - 'Sum and Substance' with Tobacco Rattle Virus
Hosta - 'Sum and Substance' with Tobacco Rattle Virus
Hosta - 'Sum and Substance' with Tobacco Rattle Virus
Hosta - 'Gold Edger' with Hosta Virus X
Hosta - 'Gold Edger' with Hosta Virus X
Hosta - 'Gold Edger' with Hosta Virus X
Hosta - 'Golden Tiara' with Hosta Virus X
Hosta - with Impatiens Necrotic Spot Virus
Hosta - with Impatiens Necrotic Spot Virus
Ivy - Phytophthora crown rot
Lamiastrum - cyclamen mite injury
New Guinea impatiens - cyclamen mite injury
Pansy - Phytophthora crown rot
Poinsettia - fungus gnat injury at stem base
Poinsettia - Lewis mite injury
Poinsettia - Lewis mite injury (close up)
Poinsettia - Phytophthora crown rot
Swedish ivy - broad mite injury
Swedish ivy - INSV (impatiens necrotic spot virus)