The Dirty Dozen

There are many reasons to grow your own food: flavor and freshness usually top the list. Pesticides are another reason.

Apple in bone hand (ulleo) Pixabay

Pros and cons of pesticides

Pesticides can make quick work of pests that damage our plants or carry plant diseases. They can also spread to unintended locations, contaminate groundwater, and interfere with the delicate balance of countless, often beneficial, life forms. How much is too much? How can we know these chemicals were used responsibly by growers halfway around the world? It’s tricky.


Healthy produce

Fresh produce is supposed to be good for us. We are urged to eat at least five servings of fresh fruit and vegetables each day. But can all the pesticides and other chemicals used in commercial agriculture be washed off? The answer is no. In many cases, pesticides are systemic, which means they are absorbed by plants. How many otherwise healthy fruits and veggies contain high levels of pesticides? The list may surprise you.

Garden harvest (congerdesign) Pixabay

Environmental Working Group

Each year, the Environmental Working Group (EWG) publishes a list of the twelve U.S. crops most contaminated with pesticides. The ‘Dirty Dozen’ are often sprayed with chemicals banned in the European Union. Did you know that peppers are sprayed with 115 different pesticides? Or, that spinach often contains twice as much pesticide residue, by weight, than any other crop tested by the EWG? According to the EWG’s 2021 Dirty Dozen, these crops are the worst when it comes to pesticides:

1. Strawberries
2. Spinach
3. Kale, collard, and mustard greens
4. Nectarines
5. Apples
6. Grapes
7. Cherries
8. Peaches
9. Pears
10. Bell and hot peppers
11. Celery
12. Tomatoes

Personally, I like using this annual list as a guide to what I will grow at home. Store-bought strawberries rarely taste as good as they look anyway, so homegrown or certified organic are the only ways to go for me. Spinach, kale, collards, and mustard greens are easy to grow and can be allowed to go seed, providing years of edible good health.


While fruit trees take time to get started, they are a good investment in your landscape and many of them can be grown in large containers. Tomatoes and peppers are regulars on my list of plants to grow, though celery has given me some trouble.


I’m not completely opposed to pesticide use. It certainly has its place. There are billions of mouths to feed, and pests feel no remorse about wiping out crops. Instead of applying broad-spectrum pesticides, we can use hand-picking, sticky barriers, and other cultural practices to manage many pests.

Black aphids on bolting spinach (Kate Russell)

The good news

On the flip side, the EWG also publishes a list of produce available in stores that score lowest on residual pesticides. This annual list is called the Green Fifteen, and here is the 2021 list:

1. Avocados
2. Corn
3. Pineapple
4. Onions
5. Papaya
6. Sweet peas (frozen)
7. Eggplant
8. Asparagus
9. Broccoli
10. Cabbage
11. Kiwifruit
12. Cauliflower
13. Mushrooms
14. Honeydew melon
15. Cantaloupe

Wax beans (Kate Russell)

My three most pest-free plants have been almonds, apples, and bush beans. My three most pest-prone plants have been Swiss chard, tomatoes, and pole beans, always with aphids. Which three plants cause you the most trouble, pest-wise? Which three need the least amount of help battling pests? Let us know in the comments.