Hello, edelweiss. The crown is the base from which all the stems originate from. In a newly planted hydrangea, there may not be much a crown yet. Maybe in a few years.
Masja blooms on old wood. That means Masja produces flower buds around the July-August timeframe. It just finished doing that. The buds are invisible at first and will open in Spring 2013 to produce blooms. Most hydrangea buds are located at the end of the stems so pruning Masja now will result in pruning off Spring 2013's blooms from those stems.
If you need to prune Masja for some reason, it should be done after it has bloomed but before July so you get to enjoy the blooms. Note that hydrangeas that have been planted in a location where they can attain their estimated size at 10 years will rarely need pruning. In other words, hydrangeas rarely need to be pruned. Masja has a compact size estimated to be 3' at 10 years. Maybe more in places with a longer growing zone.
You may also want to use a different fertilizer starting next year. Many Miracle-Gro products contain a lot of nitrogen and nitrogen not only prevents plants from going dormant in the Fall but nitrogen can also make the plant bloom less.
A single application of a slow-release general-purpose fertilizer in June should be fine where you live and last all year around. Examples: compost, composted manure, cottonseed meal or a general purpose slow-release chemical fertilizer with a NPK Ratio of 10-10-10 (like Osmocote) should be fine. The only time when you need to re-apply fertilizers is further south (in the southern U. S. states where you can fertilize in April and June or July), if you are growing hydrangeas in pots (Masja is compact enough to do this) or if your soil is defficient in some minerals. A 1/2 cup to 1 cup of compost, composted manure or cottonseed meal should be enough per application.