Taxonomically, Rhododendron is the correct genus name for all azaleas and rhododendrons. Azaleas generally have smaller flowers, bloom a bit earlier, and have much smaller leaves that may be deciduous or partly so. Rhododendrons usually have larger flowers, bloom later, and have large leaves that persist during the winter.

Bookmark Me

There are several possibilities. Voles, also known as meadow mice, may have chewed on the bark and roots near the crown of the plant. Sometimes they chew all the way around the trunk and kill the inner bark, resulting in death of the whole plant. Keep mulch away from the trunk to discourage voles. The bark may also split when there are wide fluctuations in temperature in the winter. Azaleas may begin to come out of dormancy if late winter weather is warm; if a cold snap follows, bark injury is likely, especially in sunny, exposed sites. Prolonged drought weakens plants and often results in the appearance of fungal cankers on the branches of older azaleas. Look for branches that wilt in hot, dry weather in late summer and be sure to water azaleas if drought drags on more than a few weeks. Prune out the affected branches to stop the spread of fungal canker diseases.

Bookmark Me

You undoubtedly have a problem with the azalea lace bug. This insect hatches early in spring as the new foliage begins to mature and its numbers may build to damaging levels with successive generations. Lace bugs reach their peak in late summer and do their worst in sunny, exposed sites. Spiders are important predators of lace bugs and since they shy away from sunny, hot places, plant your azaleas where there is some shade. Insecticidal soap, horticultural oil, or a systemic insecticide may spare your azaleas the damage if applied in spring when the first hatchlings are noticed.

Bookmark Me