Along with your other brassica, cabbage is a heavy feeder. We amend our gardens heavily with locally composted manure each season. Consider placing your plants out as soon as the weather, ground, is fit for cool weather crops. I space mine about 18″ apart. For best production, plant in full sun.
It’s a great idea to plant different varieties of cabbage with different maturity times so that you can extend your fresh eating cabbage harvest; rather than having to harvest more than you can eat at one time. For storage cabbage, pay attention to how long it takes for your storage cabbage to mature so you are harvesting them at the proper time. Here in Minnesota, I try to aim for a Mid-September harvest so they last a long as possible into the winter when I’m unable to harvest fresh vegetables from the garden.
I highly recommend covering your cabbage with row covers to mostly eliminate pest pressure. Nothing is more discouraging than having your cabbage, Brussels, and broccoli gobbled up by cabbage worms. Covering with a row cover keeps the white cabbage moth from laying their eggs on your plants. Problem solved. If stored properly, row covers will last for years.