Amend your soil with organic materials... it is what gardeners have been doing for centuries. You could buy a few bags of Peat Humus or composted Manure for the same price as one of those Micracle grow bags, mix that in your soil. If you have clay soil get a big bag of Spagnum Peat Moss and mix that in, it does wonders. Adding these will add organic fertilizer and improve the quality of soil in future years, make it looser and drain better.

The Miracle Grow bags are not worth it.

Well, it depends upon the particulars of what you are starting with, what crops you are trying to grow, and, most importantly, what brand and type of potting media or soil you actually buy.

To be honest, I'm NOT a big fan of Miracle Grow products. I bought a bunch of their potting mix and their moisture control potting mix last year because they had a broken bag special and it was literally dirt cheap. But, I didn't have great results with it, especially for germination of seeds.

This year, I switch to Premier Pro-Mix, and the difference in my germination rates is night and day. While I don't want to entirely blame it all on the mix, since we are also having a much warmer spring, I do feel that the MG brand stuff is too heavy and holds too much moisture, something I thought might be advantageous in some ways but proved not to be.

For containers, I would definitely recommend you go with a high quality mix like Pro-Mix, even though it costs more. Heavy cheaper mixes have a lot of issues and also weigh a lot more, something to really consider when lugging big pots or growing on balconies, rooftops, or in hanging baskets.

For general growing/soil amendment, you probably can make your own cheaper from the basic components, and some of the cheap bagged peat or manure type products are actually very good, but quality varies a LOT from manufacturer to manufacturer. I've seen some very nice, fluffy stuff in the $1.19 cheap bags, and some that is like concrete or adobe. So, always check it out first -- there are generally always broken bags sitting around where you can check out the contents.

If it's not organic MG soil mix, then there ARE chemical fertilizers in it - that's the stuff that's "good for 6 months." Flip the bag over & read the ingredients.

It's hard to be patient, but to get really good soil sometimes takes a few years. I dug several new veggie beds in the fall, knowing full well that it's going to be a while before they're fully productive. The soil is mostly builder's fill of sand + rocks, so the first step for us was sifting out the rocks!

Good garden soil has lots of organic matter in it, so the absolute best thing you can do is add lots. For most people, that's as much as they can get their hands on - several inches at least. Do this yearly, and eventually, the worms & soil bacteria will help you to make good soil. What kind of organic matter to add depends on what kind of soil you're starting with - sandy or clay. For my sand, I added manure & leaves - that's what was free, too, which was a bonus. And of course compost is amazing stuff.

If you want to get more serious about building soil, get a cheap soil test kit. It's fun to be the science wizard & find out how the nutrient levels are in your soil. Then you can add whatever your garden actually needs.

Good luck & Enjoy!