Just how finicky are hydrangea? I'd like to put one behind a row of peonies, so I'm thinking a Pia. I want MAX size 3x3! taller rather than wider. Not too moundy/spreading on the ground, either. I love them, but also know I don't want anything that takes work. I don't care about the color of the blooms I just want blooms, every year. I've never deadheaded, don't prune much, or fertilize, etc. I just want my gardener to plant it, and rain and and a little lawn watering to take care of it. Are hydrangeas subject to diseases? I've seen talk of aphids, scale, white flies, etc. I don't want any pest/insect issues. It would go in a seven yr old established bed behind short sedum autumn joy, and daylillies, already in front of the peonies. With the hydrangea in the back.....Or should I just go with more daylillies and peonies because a hydrangea is too much work?Thanks. I'm new here.