Q.How to split and replant philodendron bushes
I have several outdoor philodendron bushes and would like to split some and plant them in another par of my yard.

Philodendrons like to be slightly root bound, but you should be able to easily spilt a plant.
You will need to dig up the root ball. You most likely need to cut the plant with a knife. Replant the plants as soon as possible and provide extra water in the first couple weeks of replanting.
Here are a few links.
https://www.gardeningknowhow.com/plant-problems/environmental/root-bound-symptoms.htm
https://www.gardeningknowhow.com/houseplants/philodendron/caring-for-philodendrons.htm