@OP your plan is good, DCA to accumulate Bitcoin is a good way of acquiring Bitcoin while not burdening your financial expenses. If you wanted to get the best of your investment so that you can setup a good business with strong fundings, I would suggest to DCA for 12 years. That is 3 4-year cycle where you accumulated Bitcoin may increase by two to three folds at least.
But is it enough to run the business you are planning can't be answered, the farm land prices differs from place to place and every business is different. And you need to make the choice you want to run a business and if you do then you must have knowledge about it.
True, this is dependent on what type of business @OP wanted to set up. As far as I know there are kinds of business that does not require too much money and mostly rely on the skill of the person to make such business boom. I know a person that is able t make his business boom with a capital of only $1k. After 5 years of hard effort, they are able to setup 5 more branches of that said business.
@OP, set up a business where you are good at, what interests you and your passion. This way it won't be hard for you to give your hardest effort to build it up.