A time to look over what you have done. What has succeed and what has failed. And that other thing that failed. If you make a light weight cold frame, be prepared to search for it when it blows away. April showers bring May flowers and Mayflowers bring Pilgrims.
Looking back, I started researching planting by moon phase last year on Gardenfork discussion forums. I've hashed some thing out and have found that it's common sense. In the Chicago Land Area, Mother's Day is the start of the gardening season. About five weeks before Mother's day is the full moon. The full moon causes a gravitation pull that may be beneficial to root vegetables. Either way, it's five weeks before the latest frost and when you can-weather providing-start root vegetables, like beets, carrots, radishes.
The new moon is good for lettuces, greens, broccoli, cauliflower, and grains. This is about four weeks before the latest frost. The increased moon light helps to bring leafy vegetables up and out. I'm going to start my amaranth and quinoa, and most of my flowers about April 17th, outside from seed, weather providing.
The second quarter, a week after the new moon, is good for tomatoes, peppers, squashes, beans, and other plants that grow with seeds inside. This makes senses when looking at the traditional calendar since these are warm weather plants.
The third quarter is a time of pruning or resting. I don't think many of us take the time to enjoy what we have done. The best time I had in my garden last year was watching a pair of yellow finches go after one of my sunflowers. They were funny little birds, with the female "yapping" at the male.
By my plan. I will start, from seed outside as soon as April 3rd with the root vegetables, then wait a week, plant the greens and flowers, and finally the peppers and tomatoes. If everything freezes and fails, then I have enough seeds and sense just to try the next month.
Ps. There are exceptions. Broad Fava Beans like to be sowed super early. I'm thinking about March 27th for those.