Slow cooker vegetable soup is a simple, fuss-free meal made entirely in your slow cooker. This easy, nutritious soup is filled with savory flavor and perfect for a cozy weekend dinner at home.
Slow cooker meals are the perfect solution when you don't have time to stand over a hot stove all evening. You'll love this recipe for vegetable soup because all you need is about ten minutes of prep to get it started.
Fire-roasted tomatoes and broth serve as a base for veggies like zucchini, celery, onion, sweet potato, carrots, green beans, and corn. Seasoned with mild, savory herbs and spices, this soup has a cozy, warming flavor that the entire family will enjoy.
Serve slow cooker vegetable soup with your favorite protein, some crusty bread, or a side salad for a complete meal. Want to make your soup heartier? It's easy to customize with a can of beans, cooked ground beef, or shredded chicken. You may also love my recipe for slow cooker turkey chili!
Ingredients and substitutions
- Fresh vegetables - Onion, celery, zucchini, and sweet potato are chopped fresh and added to the slow cooker. I don't recommend omitting the onion or celery because they add flavor to the soup base. Zucchini can be substituted with summer squash, and one medium sweet potato can be substituted with two yukon gold potatoes.
- Canned tomatoes - I recommend grabbing a can of fire roasted diced tomatoes for a little added flavor. If you can't find fire roasted tomatoes, any diced tomatoes work in this recipe.
- Frozen vegetables - Adding a bag of frozen mixed vegetables helps save prep work and dicing while adding a variety of veggies to your soup.
- Broth - I recommend using regular broth, either vegetable or chicken broth, for your soup. I don't recommend using low sodium broth because this soup relies on the broth for flavor. If you need to use low sodium broth, I recommend increasing the seasoning quantities to make up for the lost flavor.
- Seasoning - Salt, pepper, garlic powder, and Italian seasoning add flavor to your soup.
Tips and tricks
Chopping your vegetables - Chop the fresh vegetables into small, bite size pieces. Think about eating your soup and how the chopped veggies will fit on a spoon.
Slow cooker size - Use a 3-quart to 4-quart size slow cooker for this recipe. If you'd like to add extra veggies to what's listed in the recipe card, I recommend opting for the larger size of the two. As written, this recipe filled my 3-quart slow cooker (shown above) about ¾ full.
Test for doneness - Use a fork to pierce through a sweet potato cube. When the potatoes are fork tender, your soup is ready.
Frequently asked questions
I recommend cooking your soup on low for 5 to 6 hours for best results, or on high for about 2.5 to 3 hours.
Yes! To make this on the stove top, warm a stock pot over medium heat and add 2 tablespoons of olive oil. When hot, add onions and celery and cook until lightly browned around the edges, about 4 to 5 minutes. Add the remaining soup ingredients and bring to a simmer. Cover, reduce heat to low, and cook until sweet potatoes are fork tender (about 20 to 25 minutes).
Leftover vegetable soup will keep for about 4 to 5 days in a tightly sealed container in the refrigerator.
Yes, vegetable soup freezes well for 3 months or more when stored in a freezer-safe container. Potatoes may fall apart slightly when frozen and thawed. To prevent this, potatoes can be omitted from the recipe or added after thawing.
Yes, feel free to add a can of rinsed and drained cannellini (or other) beans, lentils, cooked and shredded chicken, crumbled and cooked ground meat, or tofu to your vegetable soup.
Slow Cooker Vegetable Soup
- 1 medium onion, diced
- 2 celery ribs, diced
- 2 small zucchini, chopped
- 1 medium sweet potato, peeled and cubed
- 28 ounces canned fire-roasted diced tomatoes
- 10 ounces frozen mixed vegetables
- 32 ounces vegetable broth
- 1 teaspoon garlic powder
- 1 teaspoon Italian seasoning
- 1 teaspoon salt
- ½ teaspoon pepper
- In a 3-quart or larger slow cooker, add all soup ingredients: onion, celery, zucchini, sweet potato, tomatoes, frozen mixed vegetables, broth, garlic powder, Italian seasoning, salt, and pepper. Stir to combine. Cover tightly with a lid.
- Cook on low heat for 5 to 6 hours, or on high for 2.5 to 3 hours, or until sweet potatoes are fork tender. Stir sparingly (once halfway through cooking is enough).
- Serve with some crusty bread, crackers, your favorite protein, and/or a side salad for a complete meal.
- Leftovers will keep for 4 to 5 days in a sealed container in the refrigerator.
- Soup can be frozen for up to 3 months in a tightly sealed, freezer-safe container. Potatoes will soften slightly when frozen and thawed.
- Stove top directions: Warm a stock pot over medium heat and add 2 tablespoons of olive oil. When hot, add onions and celery and cook until lightly browned around the edges, about 4 to 5 minutes. Add the remaining soup ingredients and bring to a simmer. Cover, reduce heat to low, and cook until sweet potatoes are fork tender (about 20 to 25 minutes).