The last week of January to first week of February is the best time to prune ornamental grasses.
New spring growth will not emerge properly and abundantly if plants are not cut timely and severely. You can cut with sharp power or manual hedge shears, or a serrated bread knife.
Cut straight across, parallel with the ground, 3” to 4” above ground. Do not leave a nub, mound, cone, or pouffe, just a straight-across flat top, close to the ground.
You can follow up in late February or early March with a small amount of fertilizer, but be stingy, as excess fertilizer will cause ornamental grasses to grow too succulent and too fast, and they will flop over instead of standing up.
Jane Marslender says
Should I cut copper plants back now or wait. They have very few leaves on them and are about 3 or 4 ft tall?
Thank you
james gill says
I would suggest waiting till the first week of February on trimming your copper plants as well. Since copper plants are fairly cold sensitive, you would not want to stimulate new growth by pruning followed by a week of warm weather which might then be damaged by a cold snap in February. There’s always some risk you could get a cold snap in late February Or March but that’s against the odds.