Playing with new blocks

I haven't made very many of the new blocks yet, but I have to put them up on the wall to see what is happening. Here is a horizontal layout. Then I took the blocks down and tried a vertical layout. I can see I need a lot more blocks to get a good transition from light to dark. I'll probably make blocks for about 2 weeks. I tried adding in a little black and white. I think maybe I'll do one where all of the centers are black and white.
Here are the little star flowers that just appeared in my back garden a few years ago. I remember them from when I was a small child and we had them in the front yard. Out on the farm we had a huge front yard which wasn't mowed when I was real little. I think it started getting mowed the year after the bumblebee nests were in there and my older brother was almost old enough to help with the mowing.
I have 3 of these bush/trees growing in the back yard now. They just appeared about 3 years ago. I cut them down but they grow right up to 4' again. Here is a full picture and
here is a closeup of the flowers. The flowers are on the top of the branches at every spot that leaves branch off. I think I saw trees with these same flowers along the long driveway into the nursery where I got my plants. Unfortunately I was on my way out when I saw them and it is a one lane drive about 1/4 mile long so I didn't want to turn around and go back and ask if they knew what they are.