An industrial-grade, commercial acrylic or water-based paint, such as those produced by Sherwin-Williams or Benjamin Moore work best on rubber surfaces. Any paint works on rubber surfaces, such as tires, but most paint cracks or slips on the rubber over time.
Industrial-grade paints or marine paints are designed to adhere to surfaces that are not perfectly clean, a common issue when painting rubber. They are also engineered to withstand heavy wear and exposure, such as they would receive on an outdoor, recycled tire planter or other rubber surface. Industrial-grade paints from Sherwin-Williams and Benjamin Moore can be mixed to most color specifications.