With warmer weather comes first-time gardeners. Gardening can be an expensive investment for people who have more of a brown thumb than a green one. If you'd like to give gardening a try in your yard but are working on a limited budget, consider picking up flowers, herbs and other outdoor plants during the weeks between spring and summer. Spring plants will be seriously marked down (up to 90 percent off) to make room for heartier summer/fall plants, but the spring blooms will still be healthy and flourishing. So even if your garden wilts under your care, you'll learn from your mistakes without losing a lot of money. And remember: Many home and garden stores will take back plastic planters for free recycling.