Answer: This is going to depend on the weather each year and on the microclimate where they are planted. I would suggest you talk to an experienced gardener who lives close to you and see what their experience has been over the years. That would be the best indicator for what to expect in your own garden. I can tell you that in my experience the Rudbecka hirta or gloriosa daisies tend to exhaust themselves blooming but will reseed nearby; the little larkspur or Butterfly Blue delphinium is also usually considered an annual. Platycodon tends to emerge very late in the spring. Penstemon will not overwinter successfully unless it is in a very well drained location. Threadleaf coreopsis is another one that seems to start to grow later than many, look carefully for the tiniest hint of foliage as it is so finely textured it can be difficult to see at first. The phlox should show some new growth from the ground in mid spring. I hope this helps.
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