Mistakes . . . we all make them! We are not aware of some mistakes.
I ran across an excellent article on common gardening mistakes that all gardeners should read. Some I was not aware of and through the years, I have done a ton of gardening research. You never stop learning!
Click here to go to the very informative article 15 Common Gardening Mistakes Everyone Makes.
Some things to keep in mind . . .
Through my years of gardening in moderate zone 9 climate, the "rules" for winter depend on the weather. It is not a bad idea to push the limits and experiment in certain climates. For example, my best success in propagating hibiscus was during the winter when the temperatures were consistently in the 70s. For one thing, I broke the cardinal rule of not hard pruning during the winter months.
The experiment was a monumental success and I had a record number of hibiscus ready to plant in the spring and had enough to give away to other gardeners who were happy to share cuttings and surpluses of their own. You never know unless you push the limits.
The photo is a version of my garden back in 2000.