Q.Crabgrass invaded my vinca.
I have vinca around my back(north) and east side of my house. The crab grass has invaded! The vinca use to be very thick and controlled from weeds 20 years ago. It is now early Sept in SE PA. How do I dig up and start with new beds using already grown plants? How and when do I salvage my vinca to replant in new beds?

Certified GKH Gardening Expert
You probably need to start all over again with these beds by digging them up and killing off the crabgrass. You can divide your vinca and plant clumps of it elsewhere, or take cuttings and root them in preparation for replanting. You can harvest the seed pods and store the seeds for spring planting.
Here are some helpful articles:
https://www.gardeningknowhow.com/ornamental/flowers/annual-vinca/growing-annual-vinc seeds.htm
https://www.gardeningknowhow.com/garden-how-to/projects/rooting-plant-cuttings.htm
https://www.gardeningknowhow.com/garden-how-to/propagation/propgen/dividing-plants.htm
and, finally:
https://www.gardeningknowhow.com/plant-problems/weeds/crabgrass-control.htm