I'm not an expert, but I'm just supposing that the two hydrangea punches (large and 3-in-1) are made to work together ultimately. I was searching for the right coloring on hydrangeas for the 3-in-1 I just bought today and found a picture of Lacecap Hydrangea. Gorgeous!
This link might give you an idea of how to use the smallest hydrangea on the 3-in-1 for both the large punch and the largest flower shape on the 3-in-1.
Hope this helps.
BTW, I love the card sample from the Watermelon Sugar website. Thank you, thank you, thank you!