Purveyors of organic produce argue that their products are superior to non-organic fruits and vegetables. But if you're trying not to go broke (or less broke) while grocery shopping, does it really matter if you buy organic?

The good news is that you can buy some non-organic foods without missing out on whatever benefits organic produce is supposed to offer.

What does organic actually mean?

Here's how Organic.org defines organic produce:

"... grown without the use of pesticides, synthetic fertilizers, sewage sludge, genetically modified organisms, or ionizing radiation."

Not everything labeled "organic" fits that definition, and you should be careful about spending that extra money.

The U.S. Department of Agriculture has its own regulations on what constitutes organic produce and will allow something to carry the "USDA Organic" certification if it adheres to strict guidelines. They include the following:

• No prohibited substances applied to the land where the crops are grown.
• Physical, mechanical, and biological controls are used to harness pests and diseases. Ideally, "organic food is produced without using most conventional pesticides," according to the USDA National Organic Program.
• In the case of livestock, animals must have access to the outdoors year-round.

(You can read all of the guidelines here.)

Organic does not mean automatically healthier or more nutritious.

Even if you are satisfied your food conforms to the definition of organic, it does not mean the food is better for you.

Whether consuming pesticides causes cancer ... that is still hotly debated.

So why choose organic?

If you're concerned about things like added hormones in meat and dairy or pesticides in produce, then go organic. If that is something that doesn't concern you, then here is a loose guideline for which foods you can save money on by not purchasing organic.

What should you buy organic?

The typical rule is to choose organic when it comes to produce that has an edible skin, as opposed to produce that you have to peel. Andrew Weil recommends buying the organic versions of these 15 foods:

1. Apples
2. Peaches
3. Nectarines
4. Strawberries
5. Grapes
6. Celery
7. Spinach
8. Sweet Bell Peppers
9. Cucumbers
10. Cherry tomatoes
11. Snap peas (imported)
12. Potatoes
13. Hot peppers
14. Kale
15. Collard Greens

Foods you shouldn't bother buying organic

When it comes to produce you shouldn't bother buying organic, think foods with a protective rind (generally). Here's the "Clean 15," according to The Environmental Working Group:

1. Avocados
2. Sweet corn
3. Pineapples
4. Cabbage
5. Sweet peas (frozen)
6. Onions
7. Asparagus
8. Mangos
9. Papayas
10. Kiwi
11. Eggplant
12. Honeydew melon
13. Grapefruit
14. Cantaloupe
15. Cauliflower

What about meat, eggs, and dairy?

It's usually (but not always) preferable to buy organic animal products because it means the animal was not given or fed antibiotics or growth hormones — again, if you're worried about those things.

If you're looking for fewer pesticides, hormones, and antibiotics, grass-fed beef "has a slight edge" over grain-fed beef, according to The Washington Post. But the newspaper evaluated organic meat vs. non-organic meat and organic milk vs. non-organic milk and determined that organic was not better or healthier, the paper said: "Neither organic nor conventional milk contains antibiotics" and "exposure to pesticides, contaminants, or hormones is not a significant risk in either organic or conventional milk."

Not everyone agrees. Livestrong advises always purchasing organic meats and dairy products over non-organic.

It's really up to you!