Leava,

When growing in containers, the most important factor in your success is the quality of your soil-less container mix, so there is no way to save/scrimp and not spend lots of money on it. If you are not willing or able to spend the money to buy or make a high-quality soil-less mix, then don't waste your time on containers because the plants in them will not do well and will be a waste of the time and money you spend on plants and watering. So, my answer to you question basically is no, you cannot do it without the purchased ingredients needed to make a great-quality soil-less mix. If you have your own compost pile that has finished compost in it that you can use or if you have your own chipper/shredder and can make your own pine bark fines, you can save a little money, but you'll still have to buy the other ingredients.

I've linked an old thread where we discussed making a soil-less mix. The recipe I adapted for my use several years ago was one of Al's mixes from the Container Forum. I don't know how closely it resembles his current formula because I adapted it and begin making my version several years ago and almost never go to that forum any more. I adapted it to make it organic and to make it work for raising veggies in containers in our climate. I mix up vast quantities at once. My largest container is a galvanized metal stock tank that is 4' across and 3' tall, and my smallest ones are 1-gallon pots. I match the container size to the expected mature size of the plant.

To succeed with containers, you need lots of drainage holes in the bottoms of your buckets for great drainage, you need a high-quality soil-less mix and you need consistent and even watering, up to three times a day in the hottest summer weather.

Dawn

Here is a link that might be useful: Old Thread on Containers and Soil-less Mix