Repollitos are little cabbages and that’s what Jenn Klee used to call hortensias when she was a little kid. I can see the similarities with little cabbages sprouts.
Hortensias are called Hydranga by most people in the U.S., I learned, thanks to Stephanie, who also shared with us that they can be found in different colors—white, pink, lavender, and blue; all the same variety but shifting colors according to composition of the soil they are in.
Hydranga flowers are very popular in the jardín antigüeño, Antigua garden. You can see the final color of these hortensias here; make sure you pause to read the caption. Also, if you want to see what other flowers are popular in the garden around Antigua Guatemala, make sure you browse the Jardín Antigüeño series.