Japanese beetles are devouring my roses.  What can I do? 

Japanese beetles eat the foliage, fruits and flowers of more than 300 plants.  When feeding on foliage, the beetles consume the tissue between the veins, leaving a lace-like skeleton.  Flowers and fruits are sometimes devoured completely.  Roses, raspberries, grapevines, crabapples, birches and lindens are some of their favorite food hosts. 

Adult beetles are present for about six weeks every summer.  The adult beetles begin to emerge from the ground during the last week of June and new adults continue to appear throughout July.  Each beetle lives from only 30 to 45 days. 

Control of Japanese beetles is difficult.  Persistence, diligence and repeated efforts are necessary because new beetles emerge every day over a period of several weeks.  Handpicking or screening of high-value plants may be of benefit in isolated situations with limited numbers of beetles.  Remove beetles early and often to preserve the beauty of the plant and to reduce the attraction of more beetles.  Remove beetles early in the morning while temperatures are cool and the beetles are sluggish.  Collect or shake beetles into a bucket of soapy water and discard.

Spot spraying infested foliage of high value plants with a labeled garden insecticide may reduce damage for several days, but multiple applications are required to maintain control.  Check the insecticide label to make certain the plant you want to spray is listed.  Read and follow label directions.

Japanese beetle traps are widely available but have been shown to be ineffective in controlling moderate to heavy infestations.  In fact, they may attract more beetles than they catch! 

Should I water my raspberries during dry weather? 

Watering raspberry plants during dry weather can help ensure a good crop.  Adequate soil moisture levels are necessary throughout the growing season for good raspberry production.  However, the most critical time for moisture is from bloom until harvest.  During fruit development, raspberries require 1 to 1 1/2 inches of water (either from rain or irrigation) per week.  Insufficient moisture during fruit development may result in small, seedy berries. 

Which perennials grow well in wet soils? 

When selecting perennials, it’s important to choose plants that are suitable for the planting site.  Perennials that grow well in moist to wet soils include sweet flag (Acorus calamus), Jack-in-the-pulpit (Arisaema triphyllum), goat’s beard (Aruncus dioicus), swamp milkweed (Asclepias incarnata), turtlehead (Chelone species), black snakeroot (Cimicifuga racemosa), Joe-pye weed (Eupatorium purpureum), queen-of-the-prairie (Filipendula rubra), rose mallow (Hibiscus moscheutos), Japanese iris (Iris ensata), yellow flag (Iris pseudacorus), cardinal flower (Lobelia cardinalis), obedient plant (Physostegia virginiana) and spiderwort (Tradescantia species). 

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