Mulch calculator for Montana
Calculate mulch by the yard or bag for each planting bed, with depth advice for healthy plants.
Enter your project dimensions
One cubic yard holds 27 cubic feet. That is exactly 13.5 garden-center bags containing 2-cubic-foot bags. This conversion is the main reason for this calculator. Put in your bed dimensions and chosen depth below to see the cubic yards needed for bulk, along with the matching bag total for comparing a store trip. Shredded hardwood is light at around 600 lb per yard, so mulch is priced by volume and bulk delivery concerns volume, not weight.
Plan mulch for your beds
- Record the length and width of every bed in feet, then total the areas. For round beds, enter the diameter and use circle mode to calculate area.
- Use 2 inches to renew an old layer and 3 inches for bare or new beds. More than 4 inches can leave roots short of air.
- Your total shows cubic yards for bulk ordering and 13.5 bags per yard for comparing bagged mulch.
Bags (2 cu ft) = cubic yards × 13.5
Mulch coverage guide
| Depth | 1 cubic yard covers | 10 bags (2 cu ft) cover |
|---|---|---|
| 1 inch | 324 sq ft | 240 sq ft |
| 2 inches | 162 sq ft | 120 sq ft |
| 3 inches | 108 sq ft | 80 sq ft |
| 4 inches | 81 sq ft | 60 sq ft |
Common order amounts
| Project | Typical size | Depth | Cubic yards | ≈ Bags |
|---|---|---|---|---|
| Foundation beds along the house | 40 x 3 ft | 3" | 1.1 yd³ | 15 bags |
| Four tree rings | 4 ft across each | 3" | 0.5 yd³ | 6 bags |
| All beds, average yard | ≈ 500 sq ft | 3" | 4.6 yd³ | 63 bags |
| Annual refresh of the same beds | ≈ 500 sq ft | 1.5" | 2.3 yd³ | 31 bags |
| Playground surface | 15 x 15 ft | 6" | 4.2 yd³ | 56 bags |
Bulk and bags: comparing costs
Ten bags marks the point to compare options. Bags work well below that amount. Once you need more, bulk usually costs less, and free delivery means there is no need to rent a truck. Each spring, we bring out yards for customers who carried 15 bags home the prior weekend before comparing costs. Get one yard delivered, cover the extra material with a tarp, and finish the job.
Mulch depths for plant care
- After raking last year's mulch loose, add 2 inches over it.
- For uncovered ground, apply 3 inches. This layer limits weed sprouting and helps soil moisture last through July.
- Keep mulch back 3-6 inches from a tree trunk. Bark can rot when mulch touches it, and rodents can shelter there. Make a low donut shape, not a volcano.
- Do not exceed 4 inches of mulch. Deep mulch that stays wet can deprive roots of air.
- Use playground-certified chip, not landscape shred, in play spaces, with 6 inches as the minimum depth.
Select a mulch type
This calculator starts with shredded hardwood. Its fibers interlock, helping it stay put on slight slopes. Chips and nuggets may last one or two seasons longer, but hard rain can make them float and spread. Dyed mulch keeps its color while decomposing more slowly. Every option requires the same volume, so material choice changes the appearance and renewal schedule, not the quantity ordered.
Preparing for delivery
A three-yard load makes a pile roughly as large as a small car. Leave a parking-spot-sized area of driveway open and place a tarp down before it is tipped, since shredded mulch can stain fresh concrete. Spread it no later than a week or two after delivery. When a large pile sits for a month, its interior can heat up and turn sour. Plan on 30 to 45 minutes of wheelbarrow work for each yard, saving the final half-yard for overlooked beds behind the garage.
Common mulch math questions
How many mulch bags equal a cubic yard?
How many cubic feet make up a yard of mulch?
How much shredded mulch is needed?
What area will a yard of mulch cover?
What does one yard of mulch weigh?
What is the price of a yard of mulch?
Will mulch attract termites?
Can new mulch go on top of old mulch?
Other calculators
Avoid the 27-bag cart.
Order bulk shredded hardwood by the yard for driveway delivery at no charge.
