May 18, 1994

Perennial Bed Renovation

The perennial garden is a continuous source of tinkering. Gardeners will move plants from one area to another, replace those plants that didn't perform up to expectations, and thin those whose performance was more than ever dreamed possible. Sometimes the perennial bed needs more than just a cosmetic make-over. There are times when a complete renovation is in order. Perennial weeds such as quackgrass may be more numerous than the desired perennials, the soil may need improvement, or the gardener may have a new design in mind.

The Decline and Death of Cherry Trees

The heavy rainfall in 1993 has taken a heavy toll on cherry trees in Iowa. Last year's frequent rains kept the soil saturated through much of the growing season and deprived the roots of the cherry trees of oxygen. Stressed cherry trees lost their leaves in mid-summer. Some of these trees weakly leafed out again in late summer. This spring many of the cherry trees are not leafing out and are obviously dead. Others have a few small leaves. These weak trees have been severely damaged and most will probably not survive.

Unbelievable Insect Numbers, Part I

The combination of weather we experienced last summer, fall and winter has put us in a position this spring to witness emergence of unbelievable numbers of pine bark adelgids (also known as pine bark aphids). This is the insect characteristically known for causing trunks of heavily infested pine trees to appear white (as if painted). These adelgids have a fuzzy white covering similar to mealybugs and large populations can completely cover and obscure the bark.

Reasons Why Trees and Shrubs May Fail to Bloom

All trees and shrubs produce flowers. The flowers of many trees and shrubs are small and inconspicuous. Maples, oaks, and pines, for example, do flower, but they usually go unnoticed by most individuals. Many other trees and shrubs, such as crabapples and lilacs, are planted specifically for their attractive flowers. Many gardeners become concerned when their flowering tree or shrub fails to produce blossoms. The failure of woody plants to bloom may be due to several factors.