Digging up Dahlias

[Dingleroad]

The first frost have arrived and a few of the leaves have died but the plants are stll flowering. Is it time to dig up and overwinter or should I leave it a little longer ?

Also when they are eventually dug up, should I cut back the stem

[beecrofter]

You do not need to save anything above the soil surface and can wait until hard frost has mushed the foliage or dig them now.