Temperatures really begin to heat up in June -- and that typically marks the end of the planting season in this region. But continue to check out clearance sales for garden plants -- there are often good deals to be had!

Be sure and add organic matter to your soil as you plant -- it will improve your ground over time and help get your new plants off to a great start.

Watch your lettuce and other cool-season vegetables; they tend to bolt, or send up a flowering stalk once it gets hot. Once they bolt, they're usually too bitter to eat. It's probably too hot to sow new lettuce seeds in the sunny garden, but you may be able to get a small crop if you plant in the shade.

Or, replace cool-season vegetables with warm-season crops such as beans, pumpkins, squash, and corn.

Test Garden Tip: If you're growing corn, carrots, or beans from seed, you can extend your harvests by planting a handful of seeds every two weeks. That way you can enjoy the produce over a period of weeks instead of all at once.

Get more tips for maintaining a healthy vegetable garden.