Ask Mr. Sage: How to Choose Plants for Microclimates
Dear Mr. Sage,
I live in USDA Zone 7 and grow Diablo Eyelash Sage in four different parts of my yard, because I love the intense red flowers. But here's the problem: It only does well in three of the areas. It keeps dying in the fourth spot, which is a full-sun location at the bottom of a slope next to a fence. I've heard that you can have different microclimates even in a small yard. If that's happening here, what should I do?
Devil of a Problem
Dear Devil of a Problem,
Similar to water, cold air flows down slopes. It pools at obstacles such as fences and hedges unless there is an opening in the obstacle allowing the air to continue flowing. Gardeners sometimes cut holes through fence and hedge bottoms if nearby plants can't withstand a temperature drop caused by this pooling.
So, yes, it sounds like you have a microclimate in that location -- a climate that is different from surrounding areas in your yard where Diablo Eyelash Sage (Salvia blepharophylla 'Diablo') thrives. This spot likely experiences chillier winter temperatures than those of Zone 7, which is the coldest zone we recommend for this species.
To improve results, I suggest switching to another more cold-tolerant sage for that location, such as the intensely red Vermillion Bluffs® Mexican Sage (Salvia darcyi 'Pscarl') -- a Zone 5 plant.
For more information about microclimates, I highly recommend this Cornell University web page on weather and climate. However, don't hesitate to write or call Flowers by the Sea if you have more questions.
Thanks for Your Question,
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