Mixing Endurant with other chemicals is generally safe. However, it is important to contact the supplier of the products and/or perform a jar test. Consider too where you want the other products to end up. Endurant turf colorants need to remain on the leaf blade for optimal results. Do not water-in Endurant landscape colorants. Instead, Endurant needs to dry fully on the leaf blade or the surface of plants, trees, mulch or whatever is being colored. So, any products mixed with Endurant should probably be a foliar. In conclusion, mixing Endurant with other chemicals is often safe, but jar tests, checking with manufacturers and following all application instructions is important when using any chemical or material.
For more information on how to paint grass and how to apply Endurant, view this page.