will anything grow THRU a grass????

they will share... but i doubt they will take up the same space... if that makes any sense ...

perhaps your words confuse me ..????

ken

I think it would look messy. I think if you planted the clumps of grass in front of the evergreen and then bordered the area with the groundcover, that would look much better.

Fountain grass generally needs to be cut back each spring early in the growing season. Not sure how that would work with snow in summer growing up through it.

It just depends on whether you want to add some height or not as a visual interest. I understand you to mean the grasses coming up through a low ground cover, not the other way around. I would choose a more vertical grass myself, such as Little Bluestem 'Standing Ovation' or Panicum 'Northwind' and keep them spaced out, otherwise you will crowd out your silvery ground cover. Grasses would make a nice contrast against a backdrop of evergreen trees, especially if you get late afternoon sun hitting and lighting up the seed heads, that would be quite pretty. Or, you could just go with only grasses massed in and let the ground cover get taken over, again it depends on if you want to add height in front of the evergreens.

Thanks to everyone for your help. I just tore them out and it looks much nicer. I winter sowed these so had a ton of them. Now I won't have to cut them all back come springtime. That was a real job! And it probably would just get harder as they mature. Glad I got them out now instead of waiting a few more years.

There are some mature clumps of pennisetum, each with dozens of perfect, fluffy white seed heads, each plant about 3ft tall & wide up the street mass planted about 3 ft apart. Simply gorgeous, long blooming with very fine leaves, each plant is the same and very thick. It looks good every year. I'd go for it, grasses are so easy and make great ground cover. Good luck.

I think you made the right choice. Pennisetum has been a pest in my garden and the fact you were able to sow tons of them sounds like a red flag.
... but I don't know why I don't have any snow in summer, the grey leaves look perfect!