With many of my potted brugmansia seedlings frozen back to ground level, I had to take a wait and see approach to see which ones would live on and sprout back.  After cutting the frozen plants back to the ground, the soil surface was now exposed to bright sunlight and an influx of weed seeds from a neighboring field.  Normally I would apply some pre-emergent weed preventative on the surface, but I was afraid that may interfere with the plants ability to sprout back from the roots.  I tried ...