If you’re looking to add mulch to your garden beds or farm, this calculator will help you calculate exactly how much mulch you need.

Note: You can switch from inches/feet to centimeters/meters by clicking the button on the top right.

How deep should I mulch?

A depth of 2-4 inches is the general target for woody plants while 1-2 inches is enough for annuals and vegetables.

Which kind of mulch is best?

Organic mulches (wood chips, bark, pine needles, straw, compost) break down over time, adding organic matter and improving soil structure. They are an investment in soil health that may require periodic replenishment depending on your goals.

Inorganic mulches (rock, gravel, rubber) making them long-lasting and low-maintenance, but they do not feed the soil and increase reflective heat. Inorganic mulches are a poor choice for any food garden. (Technically, every garden is a food garden because even if humans aren’t eating the plants, many animals will be feeding off of them, regardless of which species of plants you’re growing).

For most garden beds, arborist wood chips are a what I recommend. If you are mulching a vegetable garden, consider something that breaks down by season’s end, like straw, leaves, or compost, so you can work it into the soil.

If you want to use wood chips in a vegetable garden, one tip that can help improve soil fertility is to let the wood chips sit in a pile for one year to begin decomposition. That way, when you add them to your garden beds they will already be beginning to break down and release more nutrients into your soil.

Important: Avoid dyed wood chips and synthetic mulches like rubber mulch at all costs. These mulches contain toxins that will leach into your soil, into your plants, and into whoever consumes the plants. Furthermore, rubber mulch is often made from tires and can cause health problems for children and animals that play in it.

Where to get free mulch?

Regardless of where you live, you can often get mulch for free by calling your local tree trimming service or arborist. These professionals often cut down and mulch trees as a service they are paid for. The wood and/or wood chips are often seen as a “waste” product and they usually have to pay or drive a long distance to dump their loads. If they can drop off the mulch and/or wood on your property, they will save a lot of money and time, making it a win-win.

If you have to buy mulch…

If you have to buy mulch, consider that bagged mulch is easy to handle and often weed-free, but it is the more expensive route. It is best for small jobs, steep access, or when you need a specific color or type that bulk suppliers do not carry. Your calculator shows bag count, so readers can price that directly.

Bulk mulch is typically mixed-species, loose, and requires transport (a truck or delivery). It is almost always cheaper per cubic yard. Many municipalities offer free or low-cost bulk mulch through parks departments or compost sites—worth checking before calling a landscape supplier.

Local landscaping companies and supply yards often offer various types of mulches, composts, and soils. Just be aware that when you buy loads of mulch, compost, or soil from these companies, they will often contain large amounts of plastics and other waste products.

Mulch from arborists tends to be much less polluted with plastics and other waste products.

Tools for Spreading Mulch

Mulch spreading is simple but physical. Depending on how much mulch you get and how far you have to transport it, you will probably want to use:

• Wheelbarrow
• A sturdy garden fork or pitchfork to load mulch into the wheelbarrow and to fluff existing mulch between applications. Shovels can work but tend to require a lot more effort.
• A rake for spreading and leveling the mulch evenly.
• Gloves because mulch is rough and splinters are real.

Things to Avoid When Spreading Mulch

When spreading mulch around trees, make sure to keep mulch 3–6 inches away from tree trunks and shrub bases so the root flare of the plant is visible. Piling mulch against the trunk traps moisture and invites rot and pests.

You want to create a doughnut of mulch around trees, not a volcano.