Yesterday I said that the first step in gardening was to define your available area. Once you've done that, you've got to define your soil. Is it horrible old hardpan full of rocks and debris? The other extreme is a soft organic filled fluffy mixture of sand clay and organic material. Most folks have something in between.
You can get a soil sample, take it to your local county extension agent and have it tested. You will then receive a reply from them recommending how many lbs. per acre of nitrogen, phophorous and potasium you need to add to your soil, but for the person with a small plot, the best thing to do is simply build up your soil to the best of your ability. I'm an organic farmer, so I add all the organic matter I can to my big garden plot. Leaves, grass clipping, kitchen waste, whatever. I just spread it around.
You can compost if you'd like and I could explain how to do that, but there are already lots of resources on the web for composting. Just remember, composting is about piling up organic matter and letting it rot. Some of those web sites will lead you to believe that you've got to be a trained chemist or biologist with mechanical skills to compost. You don't. Simply pile the stuff up and let it rot. Turn it now and then and don't let it dry out or stay too wet. It is best to keep it at least semi covered. But whatever you do remember, this aint rocket science.
Mix as much organic matter as you can into your soil. If it's really really bad like I described above, you may have to just concentrate on small areas where you know a tomato plant is going to go or a row of beans will be. I've seen old city lots that had years of gravel and debris on them turned into nice garden spots over time.
One really good method is to simply build good soil on top of nasty bad substrate. To do this, get some boards or timbers and make borders and then fill the inside with dirt and organic matter. This is called "Raised bed gardening." Back when I was a kid it was just the way some people did it and we didn't have a fancy name for it like "raised bed gardening."
Something else you can do with board and timbers is to build terraces on sloped ground. Come out a few feet from the hillside and lay a row of timbers or boards and back fill with soil. You can develop almost any piece of ground for a garden if you really want to and think creatively.
You've got to remember that this is an ongoing process. You're not going to have your best garden the first year you plant if you do it right. You will be continually improving by building up the soil.
A good source of organic matter, if you can afford it is bags of peat and manure. If you've got access to barns with horses, cattle or poultry, get your own fresh stuff. Just don't dress growing plants with fresh manure. In spring people clean out their old mulch around their flower beds. Jump on that stuff. It's great to add to a garden, expecially old hardwood mulch. I once had a cheap source of hardwood mulch and used it to mulch my vegetable garden and then turn it in the following spring or fall.
For you city folks, restaurants are a really good source of compost material. Talk to the folks at the restaurants you frequent and see if they'll let you have their organic trash. Also, coffee shops sometimes put out their coffee ground for customers to have for compost. Maybe you can get a local landscaper to drop off a load or two of clippings. They're always looking for a place to get rid of yard waste without having to haul it to the dump.
No matter where you get your organic matter that you turn into your soil, the important thing is to do it. Get as much as you can and work it into the soil as deep as you can. Now relax, don't make a labor from hell out of this. Just do the best you can and then leave it. When you plant individual plants and rows of seeds you can add a little extra to the holes or as side dressing. Like I said, this is a process that you'll work for years maybe and as time goes on it'll get better and better. Don't try to turn your soil into rich dark humus in the first year.
So, let's review:
1. Survey your space. Decide exactly how much room you've got for a garden.
2. Collect, spread and work organic material into your soil.
Good start. Above all else, enjoy yourself. Know that six months from now you are going to be reaping a harvest that will give you great satisfaction and three years from now you will be amazed at the deep brown color of the soil and how rich and musty it smells compared to when you started.