Groundcovers

This is a brief listing of some common problems that may affect specific species. Weather, climate, seasonal and stress related conditions will sometimes influence a plants likelihood of being affected by insects and disease, it is always good to know which insects may affect a particular plant so that timely measures can be taken to correct problems. This list covers plants that are mainly planted and used in zones 3 - 6.

Aegopodium podagraria 'Variegatum' - Bishops Weed - Occasionally bothered by a leaf blight in hot, humid weather, but returns to normal in drier, cooler weather.

Ajuga species & cultivars - Subject to crown rot, root rot, powdery mildew and nematodes.

Arabis species & cultivars - Rock Cress - No serious problems, although subject to the crescent-marked lily aphid. This aphid can spread mosaic and other virus diseases. Occasionally bothered by rust and mildew disease.

Arctostaphylos uva-ursi - Bearberry/ Kinnikinnick - Occasionally bothered by the rose and bearberry aphid, mildew and leaf galls.

Arenaria species - Sandwort - Seldom bothered, but subject to and occasionally bothered by powdery mildew and leaf spots.

Asarum species - Ginger - Subject to and occasionally bothered by slugs and fungus, otherwise relatively insect and disease resistant.

Astilbe chinensis 'Pumila' - Seldom bothered but subject to powdery mildew, black vine weevil, Japanese beetle and occasionally by slugs and snails.

Bergenia cordifolia & cultivars - No serious insect or disease problems.

Cerastium tomentosum & cultivars - Snow in Summer - No serious insect or disease problems.

Ceratostigma plumbaginoides - Plumbago - No serious insects or disease.

Convallaria majalis & cultivars - Lily of the Valley - Subject to anthracnose, leaf spots, root-knot nematode and lily-of-the-valley weevil. Leaf spots seem to be the most troublesome.

Coreopsis rosea - Pink Coreopsis - No serious insects or disease.

Cornus canadensis - Bunchberry - No serious insects or disease.

Coronilla varia - Crown Vetch - No serious insects or disease. (Too bad.)

Cotoneaster species & cultivars - Since it is a member of the rosaceae family it is subject to fireblight disease. Cotoneasters are also troubled by hawthorn lace bug, cotoneaster webworm, sinuate pear tree borer, pear leaf blister mite, various scales and aphids.

Cytisus species - Broom - Subject to leaf blight and leaf spot, which when left untreated can kill the plant. Also subject to white peach scale.

Dianthus species & cultivars - Pinks - Subject to crown rot, root rot. rust, and leaf spots, (all associated with damp, humid weather.) Occasionally bothered by aphids, red spider mites and black blister beetles. If you provide a bright, sunny area with good air circulation, rarely will you have any problems.

Elymus arenarius - Blue Lyme Grass - No serious insects or disease.

Epimedium species & cultivars' - Barrenwort - No serious insect or disease problems.

Euonymus - The most destructive pests are scales, and there are many kinds. Euonymus fortunei, Euonymus f. var. coloratus, and Euonymus f. var. radicans are the most susceptible. Also susceptible to aphids, thrips, anthracnose, crown gall, leaf spots and powdery mildew.

Fragaria vesca & cultivars - Strawberry - Subject to spider mites.

Forsythia species & cultivars - Nothing serious, but subject to the four-lined plant bug, Japanese weevil, northern root-knot, nematodes, crown gall and dieback.

Galium odoratum - Sweet Woodruff - No serious insects or disease. In hot, humid, wet conditions a fungus will sometimes develop which will cause the plants to brown out. This problem should clear up in drier weather.

Gaultheria procumbens & cultivars - Wintergreen - No serious insects or disease.

Genista species & cultivars - Woadwaxen - No serious insect or disease problems.

Geranium species & cultivars - Cranesbill - Occasionally bothered by leaf spots, mites, weevils and the four-lined plant bug.

Hedera helix & cultivars - Ivy - Subject to leaf spots, canker, powdery mildew, aphids, black-blister beetle, caterpillars, grape mealybugs, two-spotted spider and privet mites, eight-spotted forester moth and various scales. Spider mites and leaf spots are the most serious.

Helianthemum nummularium & cultivars - Sun Rose - No serious insect or disease problems.

Hemerocallis species & cultivars - Daylily - No serious insect or disease problems but occasionally bothered by flower thrips, which injure only the flowers, preferring yellow and other light colored blossoms. Most injurious in June, causing blossoms to become streaked.

Hosta - Subject to crown rot, slugs and snails. The thicker, corrugated leaf varieties are somewhat more resistant to slugs and snails.

Plant in well drained soil to prevent crown rot.

Houttuynia cordata 'Variegata' - Chameleon Plant - No serious insects or disease.

Hypericum calycinum - St. John’swort - No serious insect or disease problems.

Iberis sempervirens & cultivars - Candytuft - No serious insect or disease problems.

Iris cristata - Dwarf Crested Iris - No serious insect or disease problems.

Juniperus - Junipers are subject to Phomopsis blight, cedar apple rust, various aphids, beetles, borers, scales, webworm, weevil, bagworm, juniper mealybug, juniper midge, two-spotted and spruce spider mites, red cedar tortrix caterpillar, arborvitae sawfly and others. Over planted groundcover junipers, tight compact junipers, and junipers planted in too much shade or where there is poor air circulation are those most susceptible. Junipers must have full sun and good air circulation.

Lamium maculatum & cultivars - Deadnettle - No serious insect or disease problems.

Lirope spicata & cultivars - Lilyturf - No serious insect or disease problems.

Lonicera - Honeysuckle - Subject to quite a few insects and disease, including various aphids, fuller rose and potato flea beetles, four-lined plant bug, omnivorous looper caterpillar, leaf rollers, mealybugs, moths, honeysuckle sawfly, various scales, fall webworm, leaf blight and powdery mildew. Aphids and powdery mildew seem to be the most troublesome.

Lysimachia nummularia - Moneywort - No serious insect or disease problems.

Mazus reptans & cultivars - No serious insects or disease.

Pachysandra species & cultivars - Subject to Volutella blight which affects the leaves and stems, two-spotted spider mites and scales that include euonymus, oystershell and san jose scales. Pachysandra procumbens is not troubled by the same problems that affect P. terminalis.

Paxistima canbyi - Seldom bothered, but subject to leaf spots and euonymus scale. I have grown this plant in my gardens for several years and have not had any problems whatsoever.

Phalaris arundinacea & cultivars - Ribbon Grass - No insect or disease problems.

Phlox species & cultivars - Subject to powdery mildew, leaf spots, asiatic garden beetle, black blister beetle, stalk borer, six-spotted leafhopper, four-lined and phlox plant bugs, two-spotted red spider mites, root-gall nematodes, stem nematodes and scales. The most serious problem with P. subulata is spider mites, and with P. stolonifera - powdery mildew. Choose cultivars that show resistance to powdery mildew.

Polygonatum species - Solomon’s Seal - No serious insect or disease problems.

Polygonum cuspidatum compactum - Fleeceflower - No serious problems.

Potentilla species & cultivars - Cinquefoil - No serious problems.

Rosa species, hybrids & cultivars - Rose - Subject to quite a few or should I say many insects and diseases, but roses still remain a favorite with many of us. The following list, is but a few of them. Black-spot leaf disease, powdery mildew, cankers, rusts, viruses, various aphids, beetles, borers, caterpillars, leafhoppers, mites, nematodes, sawflys, scales, thrips and many more. Some of the newer hybrids and cultivars show better resistance to the diseases such as with the Meidiland™ series of roses.

Sagina subulata cultivars & hybrids - Irish/Scotch Moss - No serious insect or disease problems.

Saponaria species & cultivars - Soapwort - No serious insect or disease problems.

Sedum species & cultivars - Stonecrop - No serious insect or disease problems, although the tall varieties are occasionally bothered by aphids.

Sempervivum species & cultivars - Hens & Chicks - Subject to crown rot and rust; provide good drainage.

Stachys byzantina & cultivars - Lambs Ears - No serious insects or disease problems, however it can develop a mold-like fungus or mildew on its foliage when weather conditions become hot, humid and wet. This plant also dislikes it’s foliage being wet.

Thymus species & cultivars - Subject to fungal disease and root rot. Wooly thyme is highly susceptible to fungus disease in wet, damp weather. Plant only in full sun with good air circulation and in soil with good drainage.

Veronica species & cultivars - Speedwell - No serious insects or disease.

Vinca minor & cultivars - Myrtle - Seldom troubled but subject to leaf spots, root rot, blight, canker, dieback and northern root-knot nematode.

Top of Page

Take me to -  Trees Deciduous - Trees Evergreen - Shrubs NL Evergreen - Shrubs BL Evergreen - Shrubs Deciduous - Groundcovers - Perennials - Vines - The Bug Book Main Page