Every March I spray my yard with Killz-All and it works really well. Last year I had a terrible infestation of crabgrass. I bought some pre-emergent for that which also goes on in early spring.
Question is, can I mix the two together, or do I have to go over my yard twice?

What pre-emergent did you buy? I'm assuming you plan on backpack or boom spraying it since you spray Killz-All? Turf type and location?

Here's what I have: https://www.domyown.com/ikes-sandbur-and-crabgrass-preventer-p-23071.html

I'm in western OK, and my turf type is Bermuda and whatever else comes up.

That’s Pendimethalin and Killz-All is glyphosate. You shouldn’t have an issue tank mixing those two. I would always do a jar test. Mix a little of the two in a jar, shake it up. Give it a few minutes. If it stays mixed together and doesn’t septate or turn into sludge or a hard compound you’re good to go.

That said I’m not a huge fan Pendimethalin. You need to make multiple apps per year at a decent high rate per label. Cost per acre is pretty high. You would be better off going with Prodiamine. 65 wdg. Both are the same mode of action, but Prodiamine will give you a longer residual. You can get good results with two applications a year at a fraction of the Pendi cost. Dithiopyr would be a good option. Cost per acre should be a little cheaper than Pendi.

Pendi is a good pre emergent. But just not the most cost effective. And make sure it gets watered in soon after applying.

Here is a good write up on the 3 most popular pre’s.

Dithiopyr-vs-Prodiamine

Got mine down today. Can't water due to wind. Hope we get a good rain tomorrow.

This is all good information. I'll just plan on multiple applications and buy an extra toilet seat in case mine turns yellow.

no pre-emergent required...ZOYSIA...just took an inch off the top

Put my stuff down today hoping the rain comes tomorrow and Wednesday. Still have my sprinklers and backflow shut down.