Nothing signals the return of spring like a smelly pile of mulch.

Aside from its questionable stench, mulch plays an essential role in landscaping, from boosting curb appeal to retaining moisture and suffocating weeds.

But before you hire a landscaper or get out the wheelbarrow, you’ll first need to decide how much mulch you need.

Bulk and bagged mulch

Landscapers and garden centers sell mulch in bulk or by the bag. The most common size of bagged mulch is 2 cubic feet. Bulk mulch sells by the cubic yard. One cubic yard of mulch is equal to 13.5 bags of mulch.

When buying in bulk, you can have it delivered to your home, or pick it up if you have access to a truck or trailer. Expect to pay an additional $45 to $55 for mulch delivery.

Types of mulch

Most mulch dealers sell their own mix of “economy mulch,” which is typically a low-end variety that costs $19 to $25 per yard, or $2 to $4 per bag. This is your best bet if you need a large quantity and aren’t too particular about the appearance.

Hardwood and dyed mulches typically cost $30 to $36 per yard, or $3 to $6 per bag. To give your landscaping an extra pop of color, consider buying black, red or gold mulch.

Premium mulches, such as those made from cedar or cypress trees, can cost $40 to $47 per yard, or $4 to $7 per bag. These mulches tend to last longer and are less likely to blow away in high winds.

Determining mulch quantity

The Clemson University Cooperative Extension says one cubic yard of mulch will cover 324 square feet of ground at a depth of 1 inch. To determine how many cubic yards you need: Take the square footage of your garden bed and multiply it by the desired mulch depth and divide it by 324.

Mulch price comparison

The following breakdown shows the price comparison for buying two yards of economy mulch at $22 per yard, or $2.50 per bag.

By the bag: 27 bags x $2.50 = $67.50

Bulk: 2 cubic yards x $22 = $44

Bulk + delivery: 2 x $22 + $50 = $94

Additional mulch tips

• Add 2 to 3 inches of mulch to new beds, or 1 inch to existing beds.

• Schedule your delivery on a weekday. Mulch companies say weekend delivery slots fill up fast.

• Confirm consistency. Deals that sound too good to be true could signal the mulch company is trying to sell you an inferior product.

• Use a tarp. Place a tarp on the ground to alert the delivery driver where to unload your mulch. It also keeps the mulch dry and makes for easier cleanup.

— Mike LaFollette is a reporter at www.angieslist.com, a trusted provider of local consumer reviews and an online marketplace of services from top-rated providers.