Best Crockpot Vegetable Soup with Zucchini

If you ask me, crockpot soups are one of the best kitchen shortcuts ever invented.

This cozy vegetable soup is packed with garden-fresh zucchini and a mix of other hearty vegetables that simmer together all day long. The slow cooking brings out the natural sweetness of the vegetables and creates a rich, flavorful broth.

It’s the kind of soup that practically makes itself – just toss everything in the crockpot in the morning, and by dinner time, you’ve got a warming, homemade meal ready to go. The zucchini stays tender but never mushy, adding a nice texture to every spoonful.

It’s a simple, satisfying dish that works year-round, but I especially love it for those busy weeknights when you want something healthy and homemade without the fuss.

What Kind of Zucchini Should I Use?

For this soup recipe, medium-sized zucchini (about 6-8 inches long) are your best bet. They’re tender, have smaller seeds, and offer the perfect balance of flavor without being bitter like larger, overgrown zucchini can be. Look for zucchini that feels firm and heavy for its size, with smooth, blemish-free dark green skin. When you’re prepping them for the soup, there’s no need to peel – just give them a good wash, trim off the ends, and cut them into bite-sized pieces that will cook evenly in your crockpot.

Options for Substitutions

This soup is super adaptable and you can make several easy swaps if needed:

• Zucchini and yellow squash: You can swap these summer squashes with other quick-cooking vegetables like chopped green beans, cauliflower florets, or even chunks of butternut squash. Just note that harder vegetables like butternut squash might need a bit more cooking time.
• Baby spinach: Feel free to use regular spinach (chopped), kale, or Swiss chard instead. If using kale or chard, add them about 30 minutes before the end of cooking since they take longer to soften than spinach.
• Diced tomatoes: Fresh tomatoes work great here too – use about 2 cups chopped. You could also use crushed tomatoes or even tomato sauce for a slightly different texture.
• Vegetable broth: While vegetable broth keeps this soup vegetarian, you can use chicken broth if that’s what you have on hand. You can also use bouillon cubes dissolved in water (follow package instructions for amounts).
• Yellow onion: White onions or red onions work just as well. You can even use 2 cups of leeks (white and light green parts only) for a milder onion flavor.

Watch Out for These Mistakes While Cooking

The biggest mistake when making crockpot vegetable soup is adding all vegetables at the same time, which can leave you with mushy zucchini and undercooked onions – instead, add hardy vegetables like onions at the start and save tender vegetables like zucchini and spinach for the last 30-45 minutes of cooking.

Another common error is cutting your vegetables in inconsistent sizes, so aim for uniform, bite-sized pieces (about 1/2 inch) to ensure everything cooks evenly and is easy to eat.

To avoid a watery soup, resist the urge to lift the lid during cooking as this releases essential heat and steam, adding up to 30 minutes to your cooking time – if you must check, do it quickly and only towards the end of cooking.

For the freshest flavor, add the spinach just before serving and let it wilt naturally in the hot soup, which preserves its color and nutrients while preventing it from becoming too limp.

What to Serve With Vegetable Soup?

This light and healthy veggie soup pairs perfectly with a chunk of warm, crusty bread – I like sourdough or a rustic whole grain loaf for dunking. If you want to make it more filling, try serving it alongside a half sandwich (I’m partial to hummus and cucumber or a simple turkey and cheese). For extra protein without much fuss, you can add a scoop of quinoa right into your bowl, or top the soup with a handful of roasted chickpeas for some nice crunch. When I’m feeding a crowd, I’ll often put out a platter of cheese and crackers on the side, which always seems to make the meal feel more complete.

Storage Instructions

Keep Fresh: This veggie-packed soup stays good in the fridge for up to 5 days when kept in an airtight container. The flavors actually get better after a day or two as everything mingles together! It’s perfect for making on Sunday and enjoying throughout the week.

Freeze: Want to save some for later? Let the soup cool completely, then pour it into freezer-safe containers or bags, leaving a bit of space for expansion. It’ll keep well in the freezer for up to 3 months. Pro tip: freeze in individual portions for easy lunch prep!

Warm Up: When you’re ready to enjoy your leftover soup, just heat it up on the stovetop over medium heat until it’s nice and hot, or pop it in the microwave for a few minutes. If you’re using frozen soup, let it thaw overnight in the fridge first. The zucchini might be a bit softer after freezing, but it’ll still taste great!

Preparation Time	15-20 minutes
Cooking Time	240-480 minutes
Total Time	255-500 minutes
Level of Difficulty	Easy

Estimated Nutrition

Estimated nutrition for the whole recipe (without optional ingredients):

• Calories: 200-250
• Protein: 10-15 g
• Fat: 2-5 g
• Carbohydrates: 40-50 g

Ingredients

• 1 cup chopped yellow onion
• 2 zucchini
• 2 yellow squash
• 1 can diced tomatoes (14.5 ounces)
• 4 minced garlic cloves
• 2 containers vegetable broth (64 ounces total)
• 3 cups baby spinach leaves
• Salt and pepper, as desired

Step 1: Prep the Vegetables

Begin by peeling and roughly chopping the onion.

Next, take the zucchini and yellow squash, remove the ends, and slice them in half lengthwise.

Afterward, cut them into slices of 1/4 to 1/2 inch thickness.

Step 2: Combine Ingredients in the Slow Cooker

In your slow cooker, add the chopped onion, zucchini, yellow squash, diced tomatoes, garlic, and vegetable broth.

Stir gently to combine all the ingredients evenly.

Cover the slow cooker with its lid.

Step 3: Cook the Soup

Set your slow cooker to cook on HIGH for 4 hours or on LOW for 8 hours, depending on your schedule.

This will allow the flavors to meld together as the vegetables become tender.

Step 4: Add Spinach and Finish the Soup

A few minutes before serving, stir in the baby spinach leaves.

Allow them to wilt in the heat of the soup, which should only take a couple of minutes.

Season the soup with salt and pepper to taste.

Step 5: Serve and Enjoy

Once the spinach has wilted and you’ve adjusted the seasoning, ladle the soup into bowls.

Serve hot and enjoy the comforting and nourishing flavors!