Asters bloom in autumn and provide food for butterflies. Photo by Connie Oswald Stofko July is the time to take inventory of the blank spaces in your garden, according to Peggy Koppmann in “This Month in the Garden.” That’s one of the articles in the most recent edition of WNY Gardening Matters, produced by the Master Gardeners of Cornell Cooperative Extension in Erie County. “Perhaps a plant has died, or (gasp!), you killed it,” Koppmann said. “Maybe it got eaten by…