As winter melts into spring, gardening may be at the top of your mind. Although you may be thinking more about the prettier side of planting, like the bright blooming flowers, the mulch in your yard is important, too. Mulch offers many benefits including retaining soil moisture, regulating soil temperature, suppressing weed growth, preventing compaction, and improving soil structure.
But what kind of mulch should you use?
There are many types to choose from and each has its pros and cons.
To help you make the best choice for your yard, the Kemper Center for Home Gardening prepared this cheat sheet comparing the most popular types of mulch.
Mulch Type | Advantages | Disadvantages | Longevity | Recommended Uses |
shredded/chipped hardwood/bark | slow to decompose, adds organic material back into soil, readily available, suppresses weeds | can form a layer impermeable to water | 1-2 years | mixed shrub/perennial beds, paths |
leaves (shredded) | adds organic material back into soil, readily available, suppresses weeds | can blow away, can form a layer impermeable to water | 1 growing season | mixed shrub/perennial beds, vegetable gardens |
leaf mold (partially decomposed leaves) | adds organic material back into soil, less likely to blow away, suppresses weeds | may be difficult to source or expensive | 1 growing season | mixed shrub/perennial beds, vegetable gardens |
straw | improves soil texture, readily available | may contain weed seeds, a thick layer is needed to suppress weed growth, less ornamental, can blow away | 1 growing season | vegetable gardens |
plastic sheets (black) | suppresses weeds, warms soil | damaged by UV light, impermeable to air and water, does not add organic material back into soil, requires staking to keep in place | 1-2 years | vegetable gardens |
plastic sheets (clear) | warms soil | does not suppress weeds, damaged by UV light, impermeable to air and water, does not add organic material back into soil, requires staking to keep in place | 1-2 years | vegetable gardens |
woven landscape fabric | some permeability to air and water, suppresses some weeds | expensive, weeds can grow through the fabric, damaged by UV light, reduces air and water exchange in the soil, does not add organic material back into soil, requires staking to keep in place, makes adding or removing plants difficult | 3-5 years | paths |
Gravel/pebbles | inexpensive in the long term, fireproof, will not blow away | poor weed suppression, initially expensive, does not add organic material back into soil, difficult to remove, makes adding or removing plants difficult | permanent | rock gardens, xeriscaping |
In general, the type of mulch you need depends on how you want to use it. For most home gardeners in the St. Louis area, we recommend using an organic mulch such as shredded hardwood, shredded leaves, or leaf mold in most areas of your garden. Avoid using landscape fabrics, rock mulches, and plastic sheets except in very specific circumstances.For additional gardening help, be sure to check out the Kemper Center’s website.
Catherine Martin
Public Information Officer