Dean Allmendinger on spring gardening

      At the April 22, 2014 meeting members heard Dean Allmendinger of Dean’s Landscaping outline a number of things to watch for as spring work starts on your property.  He also answered many of the member’s questions.

      He started with the issue of snow mold, the spider web like mold that can occur on lawns under the winter snow.  Dealing with it is very easy: just lightly rake it with a leaf rake to break up the fibers.

       Another topic that is current is the Emerald Ash Borer an insect that kills ash trees and is spread by moving firewood between areas.  It has been found in St. Paul but not yet in this area possibly due to the cold winters as 20 below Fahrenheit will kill the larvae.  It is difficult to diagnose as in reality the ash tree just starts looking old before it should and then dies young.  Typically an ash tree lives 80 to 100 years.   If one looks carefully at the bark the little round bore holes (1/8 inch; 3 mm) might be seen.  Once it is detected there is a product that can be spread about the base of the tree that is a systemic treatment.

       That took him to trees in general and the more recent thinking that when planting trees one needs to leave the crown root visible or, at the most, an inch below the soil.  The old thinking was that it needed to be buried much deeper.  Oak and Cottonwood trees live about 120 years while popular lives only about 40 years.  Most of the elm is now gone from the area so there is a lot of interest in linden (basswood; tilia) trees.  They can live for centuries.  Another tree that is popular in the area now is the maple; particularly the red maples for their decorative effect.  The problem is that they like more acidic soil whereas the soil in this area is alkaline and a heavy loam that the maple does not do well in.  We are also about one temperate zone too far north for the maples though they do well in New England and Québec.

         Fruit trees were discussed and when to prune them.  They should NOT be pruned in the spring.  A good rule of thumb is to prune fruit trees during months that end in an “R”.

        He also got into some gardening techniques.  It is better to leave the foliage on perennials in the fall and “clean them up” in the spring.  Once the chance of going below zero Fahrenheit is passed they may be uncovered.  Roses should be uncovered mid-April and any dead (black) bits cut away.

         Ornamental grasses have also become popular of late.  They can grow tall and should be cut back in the fall.  Many gardeners leave about a four inch stalk to help support new growth.