Answer: Although the border is long, it isn't very wide so I think I'd stick to planting seasonal annuals and a few small perennials. Use the flowering perennials as a backbone of your planting and then tuck new annuals in and among them for seasonal color. Some annuals will self-sow, meaning you'll have new plants for free (I like that!). Ornamental kale, pansies, primroses and snapdragons are good for winter color; practically anything you like can be planted for spring and summer color (check your local garden center for ideas); mums, asters and dahlias are great for fall color. I'd plant lilies (very tall and narrow in growth habit), dwarf daylilies (year 'round foliage with summer color), dwarf nandina (heavenly bamboo), and border dahlias as the perennial backbone of the garden, then fill in with annuals. You might even grow some carrots, parsley and lettuce as early or late season annuals. They're great additions to any sunny border because their foliage is so attractive - the bonus is that you can harvest and enjoy them at the table.
Best wishes with your border garden.
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