A couple of weeks ago, or maybe three - I can't remember, I seeded a container outside with some greens: mizuna, arugula, red oak leaf lettuce, freckles romaine lettuce and black seeded simpson lettuce. Also some bulls blood beet seed. It was quite warm outside in the middle of April when I planted these but near the end of the month it got quite cold outside. One morning I checked this container and the top half inch of potting soil was frozen. At the time the plants had just started to break through the soil surface. I figured I would have to re-seed but apparently not. Everything is growing well now.