Using Stone Mulch Around Trees and in the Garden

We have several trees about 5 years old, and wonder if it is alright that we have put the plastic arbor edge around them and filled them in with small lime stone.

I must confess I am not a big fan of stone mulch and edging.  I prefer organic mulches like woodchips and shredded bark that not only suppress weeds but also moderate soil temperature and improve the soil.  Both are beneficial to your trees' health. 

The lime stone can also increase the pH making the soil more alkaline.   This is especially a problem in many areas where the ph is already high.  Increasing the soil pH can interfere with the uptake of nutrients and result in chlorosis, a yellowing of the foliage.  Over time, the plants become weakened and stressed making them more susceptible to insects, disease and early death. 

If possible consider removing the edging and widening the mulch ring around your trees.  Enlarging the mulch area will help improve the health, vigor, and longevity of your trees.  If a large mulch ring does not fit into your landscape design consider creating a bed of perennial groundcovers and low growing shrubs around your trees.  These create good growing environment.

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