So sorry for your loss. I lost my 19yr. old cat last month and am doing a garden around his grave.
I live in the Shelby/Hickory area and have lots of plants and shrubs for trade for other named plants or Miracle grow potting soil. If you are in my area and interested email me. Link included.

Here is a link that might be useful: My page

I know you will miss her; I also planted things around my pets' (two cats and four dogs so far) graves. I like ferns and native azaleas, but I think anything that you like and fits the area, i.e., sun or shade.

Husband made markers from wood, engraved with their names. We also put some trilliums and other shade loving plants there.I think about all of our wonderful pets when I walk through that area, even tho' it has been 26 years since our first loss. Making a garden around them helps keep those memories alive.

So sorry you have lost Grace. I have a 7 yr. old chocolate lab who is getting grayer everyday. I would plant bulbs and corms, which are very low maintainence. That way you will only disturb the soil once. How about reblooming daylilies for the summer? And Iris and tulips for the spring. Check the garden webs on line. I know it will make you feel so much better to plant a garden for her! Linda

dolfn,
Along with perennials, personally, I would plant a mini rose in the color red. Red for love.
You will have to water it once a week in the summer heat, but other than that, it will always come back for you because roses live for decades, and when you see the red roses, you will remember your Gracie.
I am sorry for your loss, hope you feel a little better soon.

So sorry for your loss. She was a pretty girl.

Do you have full sun where you plan to make the garden? If so, salvias in different colors would be nice, and the hummingbirds and butterflies love them, too, which is a plus.

Knowing whether it will be sun or shade would help....