This orchid belongs to the big complex around D. incarnata and can be a hybrid with D. fuchsii.
The blossoms are bigger than these of D. incarnata and have sometimes a violet hue. It blooms later than the typical D. incarnata, from june to july.
The leaves are usually without dots, sometimes D. majalis ssp. pardalina is called a dotted subspecies of Dactylorhiza praetermissa.
Remember, grouping the various Dactylorhiza species which can crossbreed profusely, is a Sysyphus work which can drive even the experts insane.
Like most Dactylorhizas, this one should not make any problems in garden culture. Place it into a wet lime bed.