Valley234

I agree with WendyLady that now you have full sun, but eventually you may not, which would change completely what will be happy in your garden. Only you know the direction the sun will shine, whether in front of, or behind the arborvitae, when they are full grown. I mean are they facing south, or north or what, on your property.

You need to make sure that those little shrub plants don't dry out too much. If it doesn't rain often enough, that you water them as their roots are shallow right now and will dry quickly in summer heat.

You could try planting seeds of flowers that really do take care of themselves till the arborvitae are larger. Note flowers that are growing at roadsides. Seeds from them will take over your bare areas till the shrubs are larger and you know what else will be happy there.