So how likely is it to freeze again? These things are, of course, difficult to be certain of.
The five previous years here have seen a freeze in May only twice (2012, 2013)on the 10th and 1st respectively. Otherwise you need to go back to 2003 to see a crazy May where it froze as late as May 19th. In that year it froze the 16-19th as well as May 6,7,8th. That May followed a somewhat similar April in that it was about as cool as this April (54.7 degrees vs 55 degrees) and kinda wet (1.41 inches of precip vs 1.6 this year).
Looking at the 10-day forecast, there is no freezing. that would take us to the 13th. In the last 20 years, 2003 was the only year to freeze after that date. Of course, there still were some real close-calls and there are still those plants to baby: basil, coleus, impatiens, begonias, zinnias and ipomea (sweet potato vine).
The ground is still cold and the moisture content is high. Pots, window boxes and baskets are much safer bets than directly into the ground. Having said all that, the "safe-to-plant" scale is at a 7.5 out of 10.
Our first crop of zucchini, cucumbers and squash have popped up!