how many bags of mulch

How Many Bags of Mulch Do You Need? (Calculator)

It’s that time of the year again. Time to mulch your yard! Are you trying to figure out how many bags of mulch to buy? It’s not easy to determine how many bags of mulch you need because bags of mulch often come in so many different sizes. Typical mulch comes in bag sizes ranging from 0.8 cubic feet to 3 cubic feet per bag of mulch. Below is a mulch calculator that will help you calculate how many bags of mulch you need for your mulching project.

How Many Cubic Feet is a Bag of Mulch?

Bags of mulch come in many different sizes. Your garden center will sell mulch in bags as small as 0.8 cubic feet to 3 cubic feet per bag.

How Deep Do You Need to Mulch to Prevent Weeds?

As a rule of thumb, mulching 2 inches deep is ideal in preventing weeds. For herbaceous plants, 2-3 inches of mulch is good, while for trees and shrubs, you can go deeper with 3-4 inches of mulch. It’s better to spread a thin layer of mulch than to go deep with your mulch. You don’t want to over mulch and suffocate your plants.

How to Calculate How Many Bags of Mulch Needed

In order to calculate how many bags of mulch you need, first measure the area of the space you are covering with mulch. This measurement does not have to be precise, just roughly measure your garden bed to get the total square feet of the area. If you are mulching around a tree, just roughly make a square around the tree and get that measurement.  

You also need to decide how deep you will cover your garden bed with mulch. Typical depth for mulch is usually 2 inches deep.

How Much Mulch is Needed for 4 feet by 8 feet Garden Bed

For example, if you have a flower bed that is 4 feet by 8 feet wide, that means you are covering 32 feet of area. Let’s say you are mulching it at 2 inches deep. That means you will need a total of 5.44 cubic feet of mulch for a 4 feet by 8 feet wide garden bed.

Formula to Calculate Mulch for 4 feet by 8 feet wide Garden Bed

  • 4 feet x 8 feet= 32 feet
  • 2 inches deep= .17 feet deep (convert to inches to feet)
  • 4 feet x 8 feet x .17 feet= 5.44 cubic feet

How Many Bags of Mulch is Needed for 4 feet by 8 feet Garden Bed

For a 4 feet by 8 feet garden bed, you will need to buy eight bags of 0.8 cubic feet of mulch or six bags of 1 cubic feet of mulch or four bags of 1.5 cubic feet of mulch or three bags of 2 cubic feet of mulch or two bags of 3 cubic feet of mulch.

How Many Bags of Mulch Do You Need for 50 Square Feet?

For 50 square feet at 2 inches deep, you will need twelve bags of 0.8 cubic feet of mulch or nine bags of 1 cubic feet of mulch or six bags of 1.5 cubic feet of mulch or five bags of 2 cubic feet of mulch or three bags of 3 cubic feet of mulch. 

While for 50 square feet at 3 inches deep, you will need seventeen bags of 0.8 cubic feet of mulch or thirteen bags of 1 cubic feet of mulch or nine bags of 1.5 cubic feet of mulch or seven bags of 2 cubic feet of mulch or five bags of 3 cubic feet of mulch. 

Below is a table with the number of bags of mulch needed for 50 square feet of garden bed.

Mulch Depth in InchesNumber of 0.8 Cubic Feet BagNumber of 1 Cubic Feet BagNumber of 1.5 Cubic Feet BagNumber of 2 Cubic Feet BagNumber of 3 Cubic Feet Bag
1 inch 75432
2 inches129653
3 inches1713975
4 inches22171296
Number of Bags of Mulch Needed for 50 Square Feet Garden Bed

How Many Bags of Mulch Do You Need for 100 Square Feet?

For 100 square feet at 2 inches deep, you will need twenty-two bags of 0.8 cubic feet of mulch or seventeen bags of 1 cubic feet of mulch or twelve bags of 1.5 cubic feet of mulch or nine bags of 2 cubic feet of mulch or six bags of 3 cubic feet of mulch. 

While for 100 square feet at 3 inches deep, you will need thirty-two bags of 0.8 cubic feet of mulch or twenty-five bags of 1 cubic feet of mulch or seventeen bags of 1.5 cubic feet of mulch or thirteen bags of 2 cubic feet of mulch or nine bags of 3 cubic feet of mulch. 

Below is a table with the number of bags of mulch needed for 100 square feet of garden bed.

Mulch Depth in InchesNumber of 0.8 Cu.ft. BagNumber of 1 Cu. Ft. BagNumber of 1.5 Cu. Ft. BagNumber of 2 Cu. Ft. BagNumber of 1 Cu. Ft. Bag
1 inch 129653
2 inches22171296
3 inches322517139
4 inches4334231712
Number of Bags of Mulch Needed for 100 Square Feet Garden Bed

How Many Bags of Mulch Do You Need for 150 Square Feet?

For 150 square feet at 2 inches deep, you will need thirty-two bags of 0.8 cubic feet of mulch or twenty-five bags of 1 cubic feet of mulch or seventeen bags of 1.5 cubic feet of mulch or thirteen bags of 2 cubic feet of mulch or nine bags of 3 cubic feet of mulch. 

While for 150 square feet at 3 inches deep, you will need forty-eight bags of 0.8 cubic feet of mulch or thirty-eight bags of 1 cubic feet of mulch or twenty-six bags of 1.5 cubic feet of mulch or nineteen bags of 2 cubic feet of mulch or thirteen bags of 3 cubic feet of mulch. 

Below is a table with the number of bags of mulch needed for 150 square feet of garden bed.

Mulch Depth in InchesNumber of 0.8 Cu.ft. BagNumber of 1 Cu. Ft. BagNumber of 1.5 Cu. Ft. BagNumber of 2 Cu. Ft. BagNumber of 1 Cu. Ft. Bag
1 inch 1713975
2 inches322517139
3 inches4838261913
4 inches6350342517
Number of Bags of Mulch Needed for 150 Square Feet Garden Bed

Mulch Calculator

What are the Benefits of Mulching?

There are many benefits to mulching. Here are 5 benefits to mulching:

1. Mulching controls weeds

Mulching is an effective weed control. By covering up bare soil with mulch, you are preventing weeds from growing in your garden. Of course, mulching does not mean you will be 100% free of weeds. Aggressive weeds will still find its way in your garden. But the good thing about having mulch is it is easier to remove weeds on mulch. The weeds are easier to pull when attached to mulch because they are not deep in the soil.

2. Mulching prevents topsoil erosion

Another benefit of mulching is it will prevent nutrients in the soil from washing off.

3. Mulch adds organic matter to soil

Mulch will eventually breakdown, adding organic matter to the soil.

4. Mulch helps retain moisture

One of the main benefits of mulching is that it helps plants retain moisture. When you mulch, your plant is more resistant to hot summer day and dry spells because the mulch helps keep moisture in.

5. Mulch provides insulation to plants

Another benefit of mulching is it provides much needed insulation and protects the plant from the winter cold.

How Often Should You Mulch?

You should mulch once a year or every other year. Mulch breaks down overtime and will need to be replenished. If your mulch looks like it hasn’t broken down yet, wait another year before adding more mulch. You don’t want to over mulch.

When to Buy Bulk Mulch versus Bag Mulch? Use Our Mulch Cost Calculator to find out if it’s cheaper to buy bulk mulch or bag mulch.

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How Many Bags of Mulch Do You Need? (Calculator)

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