How many bags of mulch for a 4-foot tree ring?

Data checked October 2026

Short answer

A 4-ft mulch ring around a 3 in trunk, 3 in deep, takes 3 cu ft — 2 bags of 2 cu ft (3 of 1.5 cu ft).

Ring area: π × (2² − 0.38²) = 12.1 sq ft. The trunk and a 3 in bare gap at the bark take 0.4 sq ft out of the circle.
At 2 in instead: 2 cu ft = 2 bags of 2 cu ft.
MSU Extension suggests extending mulch 3–6 ft from the trunk — widen this ring as the tree grows.
For 5 trees this size: 8 bags; for 10: 16 bags.
Keep it flat at 2–3 in (City of Rockville) — a mounded "mulch volcano" against the trunk holds moisture on the bark and invites rot and pests.

Adjust it to your exact job

What are you mulching?

Job

Flat rings around trees: 2–3 in deep, kept 3 in back from the bark (City of Rockville).

Size

Ring acrossouter edge

= 4' · 1.22 m

Trunkdiameter

How many trees?

MSU Extension: mulch 3–6 ft out from the trunk, so a 6–12 ft ring.

Mulch & depth

Mulch

Shredded wood with colorant. MSU Extension: wood chips and shredded wood 2–4 in.

Depth

MSU Extension: 2–4 in for dyed mulch.

Exact depth

Bag size

Check the label: the same brand comes in 1.5 and 2 cu ft bags.

How you'll buy it

You need

2× 2 cu ft bags

0.11 cu yd (3 cu ft) · 12 sq ft at 3 in · or 0.11 cu yd bulk

Cubic yards: 0.11cu yd3 cu ft
Area: 12 sq ft
One 2 cu ft bag covers: 8sq ftat 3 in
Weight, roughly: 67 lbwood mulch 400–800 lb/yd³, more when wet

Every bag size

Bags needed by bag size
Bag	Bags	Est. cost
1.5 cu ft	3	$14.94
2 cu ft	2	$7.30
3 cu ft	2	≈ $10.96

Bags or bulk?

2 × 2 cu ft bags

$7.30

Cheaper ✓ · materials, before tax

0.11 cu yd delivered

$78.81

incl. $75 delivery

Bulk becomes cheaper from about 4.9 cu yd (67 bags) — roughly 529 sq ft at 3 in. Bags work out to $49.28 per cubic yard. Your plan (bags): $7.30.

No mulch volcanoes

Spread it flat, 3 in back from the bark and no deeper than 2–3 in (City of Rockville, 2026). Mulch piled against the trunk keeps bark wet and invites rot and pests.

Shopping list

2 bags Dyed mulch (black, brown, red), 2 cu ft bags$7.30

Estimated total$7.30

Cost estimate

Tap a price to use your store's

dyed mulch, 2 cu ft bags
2 bags × $
$7.30

Materials total$7.30

Bag and bulk prices from the Mulch Pros (GA) list of Oct 22, 2026 and retail snapshots. Tap any price to use your store's.

Did this answer your question?

Compare

4 ft rings, 3 in deep, by number of trees

Trees	Cu ft	2 cu ft bags	1.5 cu ft bags	Bag cost
1	3	2	3	$7.30
3	9.1	5	7	$18.25
5	15.2	8	11	$29.20
10	30.3	16	21	$58.40

How this was worked out

The ring is a circle 4 ft across with the middle left bare: the trunk (3 in) plus a 3 in gap all round, a 9 in circle. 12.1 sq ft × 3 in ÷ 12 = 3.03 cu ft, ÷ 2 cu ft per bag = 1.52 → 2 bags.

The full method, material data and tips are on the main mulch calculator page.

Similar jobs

Other sizes people check

Sources

Data behind this answer

Mississippi State University Extension P2301 — Mulches for the Landscape — depths by mulch type (bark 2–3 in, shredded wood 2–4, pine straw 6–8, compost 2–3, rubber 2–4); rake off after 3 years · checked October 2026
MSU Extension — How to mulch — mulch 3–6 ft out from the trunk · checked October 2026
City of Rockville, MD — Say no to mulch volcanoes (May 2026) — 2–3 in deep in a flat ring; keep a 2–3 in gap at the trunk · checked October 2026
Mulch Pros — material weight & coverage (scale weights) — 2,600–2,900 lb per yd³ of stone; 1 yd³ covers 162 sq ft at 2 in and 108 at 3 in; pine straw bale ≈ 40 sq ft; single-axle ≈ 5 t, tandem up to 18 t · checked October 2026
Mulch Pros price list (October 22, 2026) — bag and bulk prices for mulch, soil, compost, #57, crush & run, pea gravel, sand; delivery $7/mi ($60 min) · checked October 2026
LawnStarter — mulch prices (updated Oct 5, 2026) — bulk $30–$135 per yd³; delivery $70–$140; 2 cu ft bags $3.25–$6.50 · checked October 2026
Roseville Rock Supply — calculator & reference table — DG ~3,000 lb/yd³, mulch 400–800 lb, topsoil 2,000–2,200 lb; order 5–10% extra; base materials up to 15% for compaction · checked October 2026
CPSC Public Playground Safety Handbook (Pub. 325) — Table 2 depths and fall heights; loose fill compresses at least 25%; 12 in initial fill for 9 in · checked October 2026
CPSC Outdoor Home Playground Safety Handbook (Pub. 324) — surfacing at least 6 ft beyond equipment in all directions · checked October 2026

Short answer

A 4-ft mulch ring around a 3 in trunk, 3 in deep, takes 3 cu ft — 2 bags of 2 cu ft (3 of 1.5 cu ft).

Ring area: π × (2² − 0.38²) = 12.1 sq ft. The trunk and a 3 in bare gap at the bark take 0.4 sq ft out of the circle.

At 2 in instead: 2 cu ft = 2 bags of 2 cu ft.

MSU Extension suggests extending mulch 3–6 ft from the trunk — widen this ring as the tree grows.

For 5 trees this size: 8 bags; for 10: 16 bags.

Keep it flat at 2–3 in (City of Rockville) — a mounded "mulch volcano" against the trunk holds moisture on the bark and invites rot and pests.

Adjust it to your exact job

What are you mulching?

Job

Flat rings around trees: 2–3 in deep, kept 3 in back from the bark (City of Rockville).

Size

Ring acrossouter edge

= 4' · 1.22 m

Trunkdiameter

How many trees?

MSU Extension: mulch 3–6 ft out from the trunk, so a 6–12 ft ring.

Mulch & depth

Mulch

Shredded wood with colorant. MSU Extension: wood chips and shredded wood 2–4 in.

Depth

MSU Extension: 2–4 in for dyed mulch.

Exact depth

Bag size

Check the label: the same brand comes in 1.5 and 2 cu ft bags.

How you'll buy it

You need

2× 2 cu ft bags

0.11 cu yd (3 cu ft) · 12 sq ft at 3 in · or 0.11 cu yd bulk

Cubic yards: 0.11cu yd3 cu ft
Area: 12 sq ft
One 2 cu ft bag covers: 8sq ftat 3 in
Weight, roughly: 67 lbwood mulch 400–800 lb/yd³, more when wet

Every bag size

Bags needed by bag size
Bag	Bags	Est. cost
1.5 cu ft	3	$14.94
2 cu ft	2	$7.30
3 cu ft	2	≈ $10.96

Bags or bulk?

2 × 2 cu ft bags

$7.30

Cheaper ✓ · materials, before tax

0.11 cu yd delivered

$78.81

incl. $75 delivery

Bulk becomes cheaper from about 4.9 cu yd (67 bags) — roughly 529 sq ft at 3 in. Bags work out to $49.28 per cubic yard. Your plan (bags): $7.30.

No mulch volcanoes

Spread it flat, 3 in back from the bark and no deeper than 2–3 in (City of Rockville, 2026). Mulch piled against the trunk keeps bark wet and invites rot and pests.

Shopping list

2 bags Dyed mulch (black, brown, red), 2 cu ft bags$7.30

Estimated total$7.30

Cost estimate

Tap a price to use your store's

dyed mulch, 2 cu ft bags
2 bags × $
$7.30

Materials total$7.30

Bag and bulk prices from the Mulch Pros (GA) list of Oct 22, 2026 and retail snapshots. Tap any price to use your store's.

Trees

Cu ft

2 cu ft bags

1.5 cu ft bags

Bag cost

$7.30

9.1

$18.25

15.2

$29.20

30.3

$58.40