Perennials: Dividing Dianthus, 0 by 2zeus

2zeus wrote:
Since y'all were so helpful with other plants, I'm asking for help on this topic. I have some dianthus I grew from seed, that are about 4-5 years old now, two varieties - "Ballad Blend" and "Chaboud's Giant Double" carnations, which our here, are perennial.

After that long winded intro, here's my question: I planted them along the front of beds that line the sidewalk going around the side of my house, and they have reached unruly clump size, a tangled messy mass of greenery on top, and dried out ugly stuff underneath.

Can dianthus be divided, technically? Or is it a matter of taking clippings, and if so, how do I go about it?

Many thanks to any and all who offer advice or anything else.