Mulch calculator for Iowa
Get bag and yard amounts for all your landscape beds, along with mulch-depth tips for plant care.
Enter your project dimensions
One cubic yard equals 27 cubic feet, or exactly 13.5 bags sized at 2 cubic feet from the garden center. That conversion drives the calculator. Put in your bed measurements and chosen depth to see both bulk cubic yards and the matching bag count for comparing a store trip. Shredded hardwood mulch is light, about 600 lb per yard, and is sold by volume rather than weight; bulk delivery is based on volume.
Calculate mulch for planting beds
- Add together the measurements of beds in feet. For round beds, measure across the diameter and use circle mode to find the area.
- For an existing mulch layer, use 2 inches as a refresh. Use 3 inches on new or bare beds. Roots can begin to lose air beyond 4 inches.
- Use cubic yards for a bulk order, or compare the result to store bags at 13.5 bags per yard.
Bags (2 cu ft) = cubic yards × 13.5
Coverage by depth
| 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 sizes
| 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 compared with bags
Ten bags marks the usual break point. Bags are handy below that amount. Once you need more, bulk is generally less expensive, and free delivery means no truck rental is needed. Each spring, we bring out yards to customers who hauled 15 bags the prior weekend, then compared costs in the parking lot. Have one yard dropped, cover unused material with a tarp, and the job is set.
Mulch depths for plant health
- After raking last year's mulch loose, add 2 inches over it.
- Put down 3 inches over uncovered ground. That depth slows weed sprouting and helps the soil stay moist during July.
- Keep mulch 3 to 6 inches away from a tree's trunk. When bark stays covered, it can decay and attract rodents. Spread it in a low ring, not a mound.
- Do not exceed 4 inches in any spot. A deep, wet layer cuts off air to roots.
- For playgrounds, use a playground-certified chip instead of landscape shred, with a 6 inches minimum depth.
Mulch types
This calculator uses shredded hardwood as its default. It locks together and tends to remain in place on gentle slopes. Chips and nuggets can last longer, but heavy rain can make them float or spread around. Dyed mulch retains its color while taking longer to break down. All types use the same volume calculation, so the quantity ordered stays the same; appearance and refresh timing are the differences.
On delivery day
Three yards of mulch forms a pile roughly as large as a small car. Make room for a parking spot on the driveway, place a tarp down, and have the load tipped there because shredded mulch can stain fresh concrete. Get it spread before about a fortnight passes. A pile sitting for a month can heat internally and turn sour. Allow 30 to 45 minutes of wheelbarrow time per yard, saving the final half-yard for overlooked beds behind the garage.
Common mulch calculation questions
How many mulch bags make a cubic yard?
How many cubic feet does one yard of mulch contain?
How much mulch is required?
What area will a yard of mulch cover?
What does a yard of mulch weigh?
What is the cost of a yard of mulch?
Can mulch draw termites?
Can fresh mulch be placed over old mulch?
Other calculators
Avoid loading a 27-bag cart.
Order bulk shredded hardwood by the yard for free driveway delivery.
