Answer: First of all, you need to determine how much sunlight the spot gets. (Remember that the trees will be leafing out soon, so you need to take the shade they'll cast into consideration.) Here are some attractive, relatively carefree, and reasonably small perennials that prefer full sun:
Coreopsis 'Moonbeam', daylily 'Little Business'' or 'Purple de Oro', lavender 'Lady', Stachys (lamb's ears; grown for its attractive, fuzzy foliage), veronica.
If the area will be shaded, please post another question via the web site and we'll come up with an alternate list for you. I hope this helps get you started.
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