Is it my imagination?

It was 7:00 am on the Cape as I started drafting today's post, and a steady rain was falling.  Again.  Usually a welcome sight to most gardeners.  But we've been deluged quite a bit this summer, and mushrooms are becoming a regular occurrence in my backyard.  Plus there's the speculation that too much water on my peppers and tomatoes is causing blossom end rot and root rot (see previous post).  Despite the convenience of being spared a trip over to the plot when other demands dictate, the question is, how much is too much?

That question piqued my interest in the effects of global warming on gardens.  In her Sustainable Gardening Blog last year, Susan Harris provided a formidable list that included increased rainfall and pollen production, as well as an increase in weedy and noxious plants (such as poison ivy), heat stress to tomatoes and other warm-season crops, and difficulties of growing lilacs, rhododendrons, and some trees.

The National Arbor Day Foundation's web site features an animation showing the boundaries of the hardiness zones moving northward between 1990 and 2006, due to the increase in temperatures.  These little changes we've been noticing over the years, whether it's more rain or diminished success growing a once-reliable staple, may be linked to something larger and more disturbing.