So I manage a lawn company (pesticide not mow) in southern texas however I'm from the midwest. The term "winterizing equipment" means something totally different from where I come from! We will continue to use our spray trucks all winter. However it does go bellow freezing down here at night at times. The owner wants me to come up with a plan to protect the engines, pumps, and hoses from possible freeze at night while parked in the shop. But my questions is, when should I be concerned about it? Space heaters would be fine but I don't feel like putting RV antifreeze through the pump at the end of the day and flushing it every morning. How cold do you think it would have to get at night for possible damage to happen to the pump and other equipment? I'm assuming the temp inside the shop with be 5-10 deg warmer than outside, at least. If it helps, I am close to the Houston area. Thoughts? Thanks!