Is there an organic method / solution to killing grass around Zinias, Nandinna's & Mini-Rose Bushes?

I am asking for a friend and have no idea the quanity nor type of grass....I don't even know if I spelled the names of her flowers correctly!

I...um...sort of 'told' her about this GREAT WEBSITE; but she says she is just too shy to join 'anything like that'. So here I am again with half-info & problems unseen!

Thanking you all in advance cuz ya ALWAYS come thru!

The safest way to do it is to lay down several layers of black and white newspaper around them and cover it with mulch. This will keep sun from the grass thus killing it, and the newspaper will eventually biodegrade.

And to add on to what Alan said,
when you do that to the top of the soil,
it ends up making the soil moister, and more plyable and if some grass still does exist,
it pulls out soooo easily when the dirt is like that...

I love weeding my beds...

Have a great day y'all!

weeds and grass are MUCH easier to pull up when the soil is a bit moist...i will pull the hose out and water a spot a bit - just to make it easier to pull the stuff up!