Ask Mr. Smarty Plants

Before we do anything else, let us suggest some amendments to your sandy soil, particularly where you want color, or flowering plants. The reason that the grasses are growing well in your soil is because that is where they belong. They have long fibrous roots that will hold the plant and stabilize the sand. In sand, water will quickly drain away, and the grass roots likely go down deep enough to tap into that water. If you want to plant different plants, even those native to Connecticut, you need to work some organic material, compost preferably, into the sand before you begin to plant. It sounds as though you basically have an extension of the beach into your area, and I'm sure you have noticed that nothing much but grasses will grow there, either.

You can find plants that fit your situation on our Native Plant Database. We will tell you how to do it and then find some examples; you can go back and make your own choices. Begin by going to our Recommended Species section, click on CT on the map, which will take you to a list of all the native plants we recommend for that state. On the set of drop-down menus on the right hand side of that page, select the kind of plant you are looking for under General Appearance. We will start by selecting on "herbs" or herbaceous flowering plants as these are the most likely to have some color. If the area you want to plant has "sun" (6 hours or more of sun a day), "part shade" (2 to 6 hours of sun) or "shade" (less than 2 hours of sun) check on that under Light Requirements. You can also indicate if you are looking for annuals or perennials under Lifespan, and Soil Moisture. We began with that, selecting "sun" under Light Requirements, since you didn't tell us what you had.

The first herbaceous flowering plant we chose is Achillea millefolium (common yarrow). You can click on that link, which will take you to the page in our Native Plant Database on that plant. You can read down through it to find out what soils it likes, what moisture and sunlight it needs, when it blooms and what color. Scrolling on down that same page to this section:

Additional resources

USDA: Find Achillea millefolium in USDA Plants
FNA: Find Achillea millefolium in the Flora of North America (if available)
Google: Search Google for Achillea millefolium

Following those links will get you even more information, including whether or not it grows in New London County. What we found out is that it is native to New London Co., had medium water use, needed sun or part shade, and liked dry soil. No mention of sandy soil. Using this method, we are going to look for a few examples, repeating search for "shrub" or "tree." You can do the same thing to expand your list.  Everything we selected was considered able to grow in rocky, sandy soils.

Herbaceous Blooming Plants for Sandy Rocky Soil in Niantic CT:

Asclepias tuberosa (butterfly milkweed)

Campanula rotundifolia (bluebell bellflower)

Monarda fistulosa (wild bergamot)

Penstemon digitalis (talus slope penstemon)

Shrubs for Sandy Rocky Soil in Niantic CT: 

Lindera benzoin (northern spicebush)

Viburnum acerifolium (mapleleaf viburnum)

Trees for Sandy Rocky Soil in Niantic CT: 

Ilex opaca (American holly)

Juniperus virginiana (eastern redcedar)

From our Native Plant Image Gallery:

Asclepias tuberosa

Campanula rotundifolia

Monarda fistulosa

Penstemon digitalis

Lindera benzoin

Viburnum acerifolium

Ilex opaca

Juniperus virginiana