My particulars:
My garden is in 5 gal. Buckets and they are set on wooden carts.
The reason is if I leave them out at night the drunks and pillbillys will tear them up.
I am growing tomatoes, pole beans and cucumbers this year as well as habanero Peppers Jalapeno Peppers and Green peppers. Also some potatoes and garlic and I thinking about carrots and lettuce this year. The carrots and lettuce I am thinking about making long narrow garden boxes and attaching to the side of the carts so I can plant them in a row. My carts hold two 5 gallon buckets each.
Since I bring them in each evening frost should not be much of a concern.
Oh and I live in Southern Ohio...
A general rule of thumb is to start your seeds 4 to six weeks before the last average frost date for your area.
Weather should be reliably warm of around 60 degrees for your warm weather plants before you transplant them to the buckets.
I your case, that will be the daylight temps as you plan on bringing them indoors at night. You will also need around 8 hours of sun daily.
Potatoes may be planted about 4 weeks before the last frost date.
Most universities have information of the average frost dates and timing of planting for their states. It would be a good idea to do a web search for the best planting dates for your state, and see what you find.
I found our Missouri Extension Service to be extremely helpful for all sorts of info including which brands of plants do well in our area.
I also sometimes buy a Farmer’s Almanac and consult their info for my region.