The temperature for planting depends on what you are planting and where.
Cool crops like spinach and lettuce for example are ok right now, but I still wouldn’t transplant them at these temps. The ones that grew during one of our earlier warm periods are surviving nicely.
Winter Wheat will continue to grow in the 30’s for another example - it just grows slower. Goes dormant when the weather gets too cold, and then grows like gangbusters when the spring warmth kicks in.
Tomatoes do not like 40 degree weather and below. Even if well established, the setting of fruit etc is inhibited when weather is in the 40’s.
Thanks for the tips on temperature. That helps! I just started a spinach cup today, and maybe, if it sprouts, I’ll put it out soon!
Soil temperature is almost as important as air temps for planting here