I'm very poor, so I hunt for no-cost and very low-cost ideas. I'd rather spend $1.79 for a seed packet than $1.79 a pound for a few days supply of a fruit or vegetable. My favorite planting supply resource is the free section of craiglist.org. There's free dirt, top soil, and free pots there very often as people move & clean out their garages, sheds, or just re-do their own yards.
I've learned to ask questions (and use Google a lot) and listen closely to the people who already know what they're doing, especially in the garden. When I find out things I didn't realize I needed to know, I link from the blog to share. It's hard to keep digging and planting anew while staring at dead leaves!
If I can learn how to get a green thumb, you can, too! Though everyone seems to do things a little bit differently, but the basics are the same. Appropriate soil, the right amount of sunshine, water, and at least a little bit of personal discipline. I don't think people need to be wealthy to buy all the "right" things, when a little patience & creativity can go a long way!
Growing plants is a bit more difficult than I thought at first, but I'm not giving up any time soon. I do still over-water & under-water but I'm learning to hold back & remember, too. Plants seem to like consistency. I've learned to be a little more patient, and not plant too many seeds at once. That way I can know what works and what doesn't without wasting too much while I'm learning.
2014 is the start of my 3rd year gardening. Almost everything I try to do is with no budget, so there's nothing fancy here! I make plenty of growing mistakes and share those, too. I hope you try to grow something, be brave and just try it, so I'm sharing how ridiculously cheap and basic (and dumb) I am about plants sometimes so you can see you don't have to be a pro to try & learn & do it!