Seriously... spend nothing on this year's garden and grow the veggies you eat every day. I used to spend as much money or more on plants/veggies and supplies to grow a few meager plants in my mini garden. While this was still rewarding (being outside, growing something), I was ready to be a little more productive.
Three things that have made all the difference in the quality and quantity of my crops: composting and rain collection and raised garden beds. While it might be a little late to do all three for this season, it's never to late to start planning for the future.
Here's what you will need to consider for your garden:
Because I've been composting faithfully for the last year, I did not have to purchase compost or additional garden soil to "refresh" my pots and beds. For the raised beds, I removed the mulch and worked the new compost into the top few layers of soil. For the pots, I dumped out the soil from last season into my wheel barrel and worked in the compost (about equal parts). Remeber to mulch around your new plants, especially if you live in a warm dry climate, it really helps conserve the moisture in your soil.
Compostable DIY Trays
To cut costs and recycle, I used egg cartons instead of buying trays. The cardboard variety of egg cartons are perfect, because they can be planted directly into the soil like compostable store bought trays. Don't eat eggs or have any egg carton's? No worries, save the cardboard from your TP roll or paper towel roll. Cut into 2 or 3 inch tubes and fill with dirt, plant seeds, place in sunny area until sprouted.
I collected seeds from veggies I bought at the grocery store/used for cooking, and used them to sprout seedlings. For veggies, I am trying peppers and pumkins from "self" harvested seeds. I also saved the seeds from my dill plant from the previous season. When you collect the seeds, make sure you store them in a dry area, until you are ready to plant. The night before planting, soak your seeds in a little bit of water.
There are a ton of great resources online for growing things from seed, scraps or existing plants. Here I used cherry tomatoes from last fall to sprout my new tomato plants. I had to harvest them late November, even the green ones and they took their time ripening...so much so that I even had a few left last month. I cut each tomato in half, placed in the soil with the exposed cut edge up, then covered with 1/2 inch of soil. Water well and cover with saran wrap for the first week or so...being careful to keep the soil moist. I am also doing this with celery, romaine lettuce, garlic, onions, and pineapple. There's a little different method for some, here's a few websites I found helpful:
Propogating, or growing new plants / herbs from existing ones. This is a great way to multiply your herbs without spending any money. This year I am increasing the number of rosemary plants in my yard. You can purchase root starters but I like to use a home-made solution that's pretty much free. Start by taking snips of an existing plant, and dip in the following solution: 1 teaspoon apple cider vinegar and 6 cups water (root excellerator). This will help the new plant get started quicker. Plant directly in to dirt, replant when the snip gets to be 3 times the size of the original container.