Hello gardeners! I'm looking for suggestions.

I have a narrow border filled with forget-me-nots and tulips in the spring. At this time of the season, they are all done and I'm hoping for some ideas of what I might succession plant to take over as they fade away? I'm thinking mainly of perennials, or annuals that are easy to direct seed.

It gets 5-6 hours of direct sun and the soil is sandy, double-dug with lots of compost and well drained. It gets watered as needed. We are located close to the sound on the west side. Slugs are always a problem. I am partial to shades of blue and pink flowers mostly along with shades that go with them.

Anyone have some ideas that come to mind? Please help!