How to Make Vegetable Broth (From Fresh Veg or Scraps)
Soften onions, carrots and celery in a little oil, add about 3 litres of water with herbs, peppercorns and any vegetable scraps you've saved, and simmer gently for about an hour, then strain. You get 2–2.5 litres of light, savoury broth for soups, risotto and stews.
Cool it quickly in shallow containers, keep it 3–4 days in the fridge and freeze the rest. Vegetables are low-acid, so broth can only be canned in a pressure canner, never a water bath. It is a tasty base, not a detox or a source of much nutrition.
Ingredients
- 1 tbsp Olive oil
- 2, quartered (skins on for a deeper colour) Onions
- 3, roughly chopped Carrots
- 3 sticks, roughly chopped, with leaves Celery
- 1 leek, or a handful of mushrooms, or ½ fennel bulb Leek, mushrooms or fennel (optional)Mushrooms add a meaty depth; fennel a light aniseed note
- 3–4 cloves, bashed Garlic
- 2–4 handfuls Saved vegetable scraps (optional)Clean peelings and trimmings of onion, carrot, celery, leek, mushroom, parsley stalks and herb stems; see the FAQ for what to leave out
- 2 bay leaves, a few sprigs of thyme, a small bunch of stalks Bay leaves, thyme and parsley stalks
- 1 tsp Black peppercorns
- About 3 litres (to cover the vegetables by 5 cm) Cold water
- To taste, when you use it SaltLeaving it unsalted lets you season the final dish and keeps salt down
Equipment
- Large stockpot of at least 5 litres
- Wooden spoon and ladle
- Large sieve, and a fine sieve or muslin for a clearer broth
- Large bowl, and a sink or bigger bowl for an ice-water bath
- Shallow lidded containers, freezer bags or ice-cube trays
Method
Wash and chop the vegetables
Scrub the vegetables and chop them roughly; there is no need to peel. Rinse saved scraps well, and throw out anything slimy or mouldy.
Soften the base
Warm the oil in the pot over a medium heat and add the onions, carrots, celery and any leek or mushrooms. Cook for 8–10 minutes, stirring now and then, until they start to soften and colour at the edges. This gives a fuller flavour; you can skip it for a lighter broth.
Add water and aromatics
Add the garlic, scraps, bay, thyme, parsley stalks and peppercorns, then pour in cold water to cover everything by about 5 cm.
Simmer for about an hour
Bring it to the boil, then turn it down to a gentle simmer and leave it partly covered for 45–60 minutes. Longer cooking doesn't help much: after about an hour the flavour can turn flat or bitter.
Strain
Pour it through a large sieve into a bowl, pressing the vegetables lightly with the back of a ladle, then through a fine sieve or muslin if you want it clear. Compost the vegetables.
Cool it fast
Refrigerate it within 2 hours of cooking. A big pot cools slowly and lets bacteria multiply, so divide the broth into shallow containers, or stand the bowl in a sink of iced water and stir, then put it in the fridge.1
Store and reheat
Keep it in the fridge for 3–4 days and freeze the rest in portions; freezer bags laid flat or ice-cube trays work well. Frozen leftovers stay safe indefinitely but are best used within 3–4 months. Reheat soups and broths by bringing them to a rolling boil.1,2
Pressure-can it only with tested instructions
Vegetables are low-acid foods, so broth can only be canned safely in a pressure canner, which reaches 116–121°C (240–250°F). Follow the National Center for Home Food Preservation's tested soup instructions exactly; if you don't have a pressure canner, freeze it instead.3,4
Safety
- Refrigerate within 2 hours. Split a big pot into shallow containers so it cools quickly1
- Keep it 3–4 days in the fridge at 4°C (40°F) or below, and freeze the rest1,2
- Never can broth in a water bath or by 'open kettle': vegetables are low-acid and botulism spores survive boiling. Use a pressure canner3
- Reheat until it reaches 74°C (165°F); bringing it to a rolling boil is the simple check1
- On a potassium-restricted diet for kidney disease? Cooking water draws potassium out of vegetables, so ask your dietitian about broth6
Variations
Keep a bag in the freezer and add clean onion, carrot, celery, leek and mushroom trimmings and herb stalks. When it is full, simmer the contents with fresh water and a bay leaf for an hour.
Roast the onions, carrots, celery and mushrooms at 200°C (180°C fan, 400°F) for 30–40 minutes until browned, then simmer as usual. It gives a darker, richer broth.
Add a handful of dried mushrooms and a strip of kombu seaweed for a deeply savoury broth. Lift the kombu out after 10 minutes, before the water boils hard, or it can turn slimy.
Add a thumb of sliced fresh ginger and a bunch of spring onions for the last 20 minutes. Good for noodle soups.
Does it actually work?
Vegetable broth is a flavour base, mostly water. The fibre and the bulk of the vegetables are strained out, so a mug of broth adds little beyond flavour, a little salt if you add it, and some minerals.
Those minerals do move into the water: a 2021 review of 65 studies found that boiling reduced the potassium in vegetables, which is why people on low-potassium diets for kidney disease boil vegetables and throw the water away. So homemade broth carries some potassium, but nobody has measured how much a typical home broth holds.
There is no evidence that vegetable broth detoxes the body, boosts immunity or causes weight loss. Shop-bought broths and stock cubes can be salty, and the NHS advises adults to have no more than 6 g of salt a day, so leave homemade broth unsalted and season the finished dish.6,5
Evidence ratings for what goes in: Olive oil, Black pepper (piperine), Sea salt.
Questions people ask
How long should I simmer vegetable broth?
About 45–60 minutes at a gentle simmer is enough to draw out the flavour. Unlike bone broth, there is no collagen to extract, and much longer cooking can make vegetable broth taste flat or bitter. These are common kitchen times rather than tested figures.
What vegetables should I not put in broth?
Cabbage, broccoli, cauliflower, Brussels sprouts and turnips can make it sulphurous and bitter, beetroot turns it pink, and potatoes and other starchy veg make it cloudy. Leave out anything slimy, mouldy or past its best: broth is not a way to use up spoiled food.
How long does homemade vegetable broth last?
The USDA gives 3–4 days in the fridge for leftovers, and the FDA's storage chart lists vegetable soups at 3–4 days in the fridge. Freeze anything you won't use by then; frozen it stays safe indefinitely and is best within 3–4 months.
Can I can vegetable broth in a water bath?
No. Vegetables are low-acid foods, and botulism spores are very hard to destroy at boiling-water temperatures, so low-acid foods must be processed in a pressure canner.
The NCHFP's tested soup instructions use a hot pack and 60 minutes for pints or 75 for quarts, at a pressure set for your altitude and canner. If you can't follow tested instructions exactly, freeze it.
What is the difference between vegetable broth and vegetable stock?
In everyday cooking the words are used interchangeably. Some cooks call the lightly seasoned version broth, for sipping or soup, and the plainer, unsalted version stock, for building sauces and risotto. This recipe works as either.
Sources (6)
- Regulator USDA Food Safety and Inspection Service. Leftovers and Food Safety.
- Regulator US Food and Drug Administration. Refrigerator & Freezer Storage Chart. 2018.
- University extension National Center for Home Food Preservation (University of Georgia). Ensuring Safe Canned Foods.
- University extension National Center for Home Food Preservation (University of Georgia). Soups (canning vegetables and vegetable products).
- Public health body NHS. Salt in your diet.
- Systematic review Batista RAB, Japur CC, Prestes IV, Fortunato Silva J, Cavanha M, das Graças Pena G. Potassium reduction in food by preparation technique for the dietetic management of patients with chronic kidney disease: a review. J Hum Nutr Diet. 2021.
Educational only. Patch-test anything new on your skin, and stop if it irritates.
Reader notes
Experiences and questions from readers, read by an editor before they appear. They are personal accounts, not evidence, and are not medical advice.