
Certified GKH Gardening Expert
The tulips should be fine, but if any are blooming, the cold may affect the blooms, though the bulb itself will be fine and regrowth shouldn't be a problem. You shouldn't have to cover your plants, but if the plants are in an area that can be easily covered and you feel more at ease doing so, then you can toss a sheet over them at night but remove it during the day. This article should also help: https://www.gardeningknowhow.com/plant-problems/environmental/protect-plants-in-freeze.htm Normally, established tulips are tough, tolerating and surviving well in winters. I wouldn't write them off just yet.