Ornamental grasses - Pruning/Dividing

[Curlykale]

The ornamental grasses took over my gravel garden when I blinked. When I planted them the garden looked a bit oriental, just specimen grass and bamboo plants dotted amongst the gravel, but now they are triffids and I can't even see the gravel. There are several different varieties and some of them are 6/7 feet high.

I need to get them down to a manageable and attractive size again.

Should they be pruned/cut back regularly? If so how far should I cut them back and when is the best time to do it? Or should I dig them up and divide them? If so, should I trim them first?

[Two_Sheds]

A cursory Gaggle gave me lots of answers ranging from Feb to July !

I trust the RHS though, which says to do it in the spring

[kentvegplot]

If you need to cut down the bamboo as well as the grasses, it's best to take some of the taller stems right off at the base - it looks awful if 'pruned' to (say) 3' tall, and the resulting stubs are very sharp.

Agree with TS, don't divide grasses until Spring (but you can move whole plants now). Just think how lovely they will look with frost on (!)

[Curlykale]

thanks guys