You could slightly enlarge the holes in the spraybar, this would reduce the velocity of the water.
Slightly closing the output (only) valve from the filter would also reduce the amount of water exiting the canister but would also reduce the amount of filtered water turnover.
You could also make a longer DIY spraybar if you are handy. This would allow the output water to be spread over a longer area of the tank and reduce the velocity that is blowing your plants around. It would also provide better circulation throughout the tank.
Eheim Pimpette #270
Eheim Pro II 2028; Classics Series -2215, 2217, 2260, 2262; Pro 2229 Wet/Dry