After checking plant times for my zone I have seen some disturbing discrepancies. The times are all over the place. I have seen one to say not to plant tomatoes until March and other saying not to plant them until may! 2 people who garden every year, we know these new planting times are incomplete error. So do the steps.
Make sure the ground temperature, about where your seeds or plants should go, and make sure the Brown is at least 40 to 50 degrees. If it is a little cooler than that, that's OK because your seeds will not germinate until it is warm enough. Plants are a different story. Check your temperature!
Also in the spring, check several weather forecast at least 7 days in advance. Sometimes God likes to throw a curveball at us and give us a Frost late. This may not hurt your seeds but it will send you back to the gardening center for more plant yes they are not prepared for the cold. Cabbages, Cauliflower, broccoli, onions, garlic, lettuce, spinach, and mustard greens are plants that can take a pretty good Frost and survive. I have grown collard greens and spinach until late December.
Tomatoes, peppers, squash and other warm weather plants will die a miserable death that you cannot bring them back from.
So learn what a cold weather and warm weather crops are. Many times cold weather crops will be done when is time to put in warm weather crops.
Just because you're planting guide says to plan on a certain day does not mean it that day is good enough for your seeds and plants.
If you see me planting early in my Facebook group, I would ask why I am doing it at that time. For the most part I plan on time what some plants I try to get a head start on and I have tips and tricks to get me going.