The frost did indeed come last night. This morning the field was blanketed in a layer of ice.
Spinach is hardy enough to tolerate the ice so it spent the night uncovered. Once the sun melts the ice off later today these little plants will bounce back.
Below is a stray zucchini plant that slipped out of its row cover and got hit by the frost. Unfortunately, zucchini is much more fragile than spinach so this plant is a goner.
Happily, the rest of the zucchini plants were tucked under their cozy row cover and made it safely through the icy night.
The weather forecast is predicting an end to this late May chill today, and the morning has already been warming up nicely. The row covers will come off this afternoon before the plants heat up too much.