How many inches deep should mulch be?
2 to 3 inches, and never against the bark.
The depth of the layer
2 to 3 inches
Never more than 3. Deeper mulch starves roots of oxygen.
- 3 inchesback from a tree trunk. Bark kept moist under mulch decays.
- 1 inchat most around boxwood and other shallow-rooted plants.
How thick should a layer of mulch be around trees and shrubs?
Mulch should be laid 2 to 3 inches deep, and never more than 3. Keep it about 3 inches back from tree trunks, never touching bark. Boxwood and other shallow-rooted plants get 1 inch at most. Over old mulch, add only enough to reach that depth again.
Source: University of Maryland Extension
Adding new mulch over old.
Measure the old layer
Over time, added mulch can build up to five inches or more.
Work in old mulch
It can be worked into the bed or moved elsewhere in the garden.
Add the difference
New mulch only brings the layer back to depth.
Water through it
A light watering may only wet the mulch.
What one cubic yard of mulch covers
162 sq ft
At 2 inches deep.
We install mulch and beds.
Mulch and planting beds
New beds built, old ones cleaned up.
Lawn and landscape care
Mowing, cleanups and seasonal work.
GuideMaryland lawn calendar
Mowing, seeding and leaf dates.
Questions
How do you add mulch on top of existing mulch?
Add only enough to freshen the old layer, and keep the total depth at 3 inches or less. Old mulch can first be gently worked into the bed or moved elsewhere in the garden. Bark at the base of a trunk stays uncovered, with no mulch heaped against it.
How many yards of mulch do I need?
Multiply the bed's square feet by the depth in inches and divide by 324 to get cubic yards. One cubic yard covers 324 square feet at 1 inch, 162 at 2 inches and 108 at 3. A 200 square foot bed at 2 inches needs about 1.2 cubic yards.
How often should mulch be put down?
Only as often as the layer thins. Organic mulch breaks down over time, and it is replaced only as needed to keep its original depth. Adding more as a routine can build it up to five inches or more, which harms plants.
When should you mulch in Maryland?
In flower beds, mulch after the plants are in and the soil has warmed up, while the soil is damp. A new tree or shrub is mulched right after it is planted and watered.
Can I mulch in the fall?
Yes, mulch can go down in fall. Winter mulch goes on perennials in late fall, after several killing frosts. Put on too early, the warmth it holds can start new growth and badly damage the plant. Trees and shrubs planted in fall are mulched as part of planting.
Get a free estimate.
We install mulch, build new planting beds, clean up old ones, and put in shrubs and plants. Estimates are free.
