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Spider Mites - Flowers and Groundcovers

Back to Common Problems of Annuals, Bulbs, Groundcovers, Perennials, and Vines Publication: (PDF) HG 13 Spider Mites Spider mites are very tiny plant pests that are related to spiders. They feed only on plants. The colors may be reddish or light green with two dark spots. They are about the size of...

Soft Scales - Groundcovers

Dieback on sweetbox from cottony camellia scale. Scales are sucking insects that attack some groundcovers. Heavy infestations may cause leaf yellowing, stunting and dieback. Soft scales appear as raised bumps on leaves and stems, vary in color and can be scraped off. They may be over 1/3 inch when...

Slugs and Snails - Flowers

Slug damage on hosta. Back to Common Problems of Annuals, Bulbs, Groundcovers, Perennials, and Vines Publications: (PDF) HG92 Slugs and Snails (PDF) FS 822 - Slugs - Managing Slugs in the Garden and Beyond Slugs and snails can be troublesome pests in the garden. Both eat large, ragged holes in the...

Armored Scales - Groundcovers

Euonymus scale on pachysandra. Scales are sucking insects that attack groundcovers such as lirope and pachysandra. Heavy infestations may cause leaf yellowing, stunting and dieback. Armored scales are small, about one-eighth inch, flat, disk-like, circular, elongate or oystershell shaped. The color...

Fungal Leaf Spots - Annuals, Bulbs, Groundcover, Perennials and Vines

Back to Common Problems - Annuals, Bulbs, Groundcovers, Perennials and Vines General Leaf Spots Fungal leaf spots are common on many herbaceous flowering plants, however some are more devastating than others. Experience and regular monitoring will alert gardeners as to the seriousness of the...

Bacterial Leaf Spots - Annuals, Bulbs, Groundcovers, Perennials, and Vines

Back to Common Problems - Annuals, Bulbs, Groundcovers, Perennials, and Vines Bacteria are single-celled, microscopic organisms, bounded by a cell wall, that cause plant diseases. Bacteria are much smaller than fungi and nematodes but can cause severe symptoms. Bacterial pathogens can cause soft...

Bacterial Crown Gall - Flowers

Back to Common Problems - Annuals, Bulbs, Groundcovers, Perennials, and Vines Crown gall is caused by a soil-inhabiting bacterium, Agrobacterium tumefaciens , which occurs worldwide and attacks over 600 plant species in more than 90 plant families. The disease severity can vary depending on the...

Aster Yellows - Flowers

Back to Common Problems - Annuals, Bulbs, Groundcovers, Perennials and Vines Aster Yellows causes a general yellowing and stunting of the plant. Often there are other symptoms on older plants such as witches brooming, abnormal, massed, brush-like development of many weak shoots arising at or close...

Anthracnose - Annuals, Bulbs, Groundcovers, Perennials and Vines

Back to Common Problems - Annuals, Bulbs, Groundcovers, Perennials and Vines Anthracnose symptoms typically appear as dark-colored spots or sunken lesions that can quickly run together to form irregular dark lesions that cause rapid blighting of leaves or stems. This blighting can result in severe...

Toxic or Sour Mulch/Wood Alcohol

Back to Common Problems - Annuals, Bulbs, Groundcovers, Perennials, and Vines Occasionally the leaves of shrubs, annuals or perennials may become bleached, scorched or chlorotic after a fresh application of wood mulch products. This problem is caused by "Wood Alcohol Syndrome", also called "Sour...

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