Answer: Your mother may have grown a smaller variety of sedum, and in fact sedums as a group should do well in that type of location. Another possibility would be the golden flowered perennial Alyssum , the yellow flowered Corydalis lutea, and Lady's Mantle, or Alchemilla mollis. Smaller types of perennial Dianthus and Thyme are other possibilities to consider. These will not necessarily however protect against the chipmunks who tunnel; the tunneling can actually cause structural problems so do be sure to keep an eye on their activity.
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