Is worm castings profitable to sell on Amazon United States?

The niche generates $2.0M/yr across 27 tracked products. 1 of 1 products launched in the last 360 days are still selling. 90-day search growth is +8.3%. Flapen's verdict: Launch it (62/100).

How competitive is the worm castings niche?

14 brands and 35 sellers compete. The top 5 products take 54% of clicks and top 5 brands hold 83% of demand.

What do buyers complain about in worm castings?

Top complaints mined from reviews: Quality-Overall, Value For Money, Plant Growth. The return rate is 0.2%.

When does demand for worm castings peak?

Demand peaks in Mar–Apr–May; the busiest month runs 3.3× the quietest.

What does it cost to enter the worm castings niche?

Listings span $7.50–$67.40; the average listing price is $22.07 (sweet spot $15–$100). The average incumbent carries 1,936 reviews — the moat a new listing must climb.

worm castings

Launch it

A $2.0M/yr market growing +8.3% this quarter with returns at 0.2% — clears our launch bar.

Returns

Incredible0.2%

return rate — above 6% kills the launch gate

Market size

Great$2.0M

$2.0M/yr · 959K searches

Avg price

Great$22.07

avg listing price — sweet spot $15–$100

Price range

Great$7.50–$67.40

cheapest to priciest tracked listing — scored on the share inside $15–$100

Conversion

Great9.2%

search→purchase rate — share of searches ending in a sale

Competition

Good54%

top-5 click share — leaders hold, buyers still browse

Review moat

Okay1,935.96

avg incumbent reviews — the moat a new listing must climb

Brand share

Okay83%

top-5 brand share — brands hold most of the demand

Growth

Okay+8.3%

90-day search growth — must beat 0% to launch

Quality gap

Bad4.7★

avg incumbent rating — lower means beatable quality

According to Flapen's Amazon United States niche tracking, worm castings is a $2.0M/yr Amazon United States market (959K searches/yr). The top 5 brands hold 83% of demand. Demand peaks in Mar–Apr–May. Verdict: Launch it — 62/100.

Data updated Jul 15, 2026 · scored weekly · How we score niches

worm castings market data

Units sold / yr: 80K–100K; avg 4,000–5,000/product
Revenue / yr: $1.8M–$2.2M; units × avg price
Launch success: —; 1 of 1 new (360d)
Conversion rate: 9.2%
Avg BSR: #479
Page quality: 0%
Prime: 67%
Sponsored: 89%
Out of stock: 4.9%
Avg brand age: 65 months
Avg seller age: 157 days

Competition & brand share

The top 5 products take 54% of clicks — established leaders, but buyers still shop beyond them.

Brands

14 rising

Sellers

Top-5 brand share

83%

Top 20: 97%

Top-5 click share

54%

Top 20: 92%

Open market

14%

Wiggle Worm28%
BRUT WORM FARMS27%
plantonix13%
Back to the Roots10%
Earth Science5%
--3%
Open — no brand owns it (8 brands, 14%)

Demand & seasonality

Weekly Amazon search volume, last 104 weeks — +8.3% search growth over the last 90 days.

Peak months: Mar, Apr, May · busiest ÷ quietest = 3.3×

Open Trend

Top worm castings search terms

worm castings490K/yr +3.4%9.3% conv.
worm castings for gardening82K/yr +75.8%10.6% conv.
earthworm castings75K/yr +26.9%7.9% conv.
worm castings for plants105K/yr -48.2%8.6% conv.
humus de lombriz para plantas38K/yr +36.0%3.2% conv.
worm casting36K/yr -0.1%6.9% conv.
wiggle worm castings14K/yr +34.4%9.1% conv.
worm castings organic fertilizer16K/yr +11.1%8.7% conv.
organic worm castings15K/yr +1.9%8.7% conv.
humus de lombriz13K/yr +29.0%2.7% conv.

All search terms

Top worm castings products on Amazon

Each bubble is one product — market share against review moat; bubble size tracks estimated sales, color grades how beatable the incumbent looks.

Beatable (≤4.3★) Contested Strong incumbent (>4.7★)

All 27 tracked products in this niche — three views at once, no toggling.

Top sellers

by 90-day click share

Brut Organic Worm Castings for Plants 5 LB Natural Nutrients Fertility Builder Plant Food for Potting Soil and Garden Soil Indoor and Outdoor Use

BRUT WORM FARMS$15.444.8★5,828 rev

Wiggle Worm 100% Pure Organic Mineral-Dense Worm Castings Fertilizer 30lbs - Improves Soil Fertility and Aeration for Growing Better Houseplants Vegetables and More

Wiggle Worm$34.244.8★1,817 rev

Back to the Roots Organic Worm Castings for Plants Natural Fertilizer and Soil Enhancer for Gardening Made in the USA 5lb

Back to the Roots$14.874.8★906 rev

Wiggle Worm 100% Pure Worm Castings Plus Worm Egg Material 40lbs - Fertilizer and Soil Amendment for Indoor and Outdoor Gardening to Improve Soil Fertility and Aeration - 100% Organic and Odor Free

Wiggle Worm$41.544.6★984 rev

Brut Organic Worm Castings for Plants 12 LB Natural Nutrients Fertility Builder Plant Food for Potting Soil and Garden Soil Indoor and Outdoor Use

BRUT WORM FARMS$24.114.8★5,828 rev

Newest

by launch date

Wrigglebrew Organic Liquid Fertilizer Concentrate from Worm Castings. Non-toxic All-Purpose Plant Food for Gardens Vegetables Fruits Houseplants Seed Starters and Ornamentals. (16 Fluid Ounces)

WriggleBrew$10.00174 rev

12mo ago

Earth Science RevitaSoil 4lb Up to 16 Sq. Ft. - Premium Organic Soil Revitalizer - Natural Nutrients & Earthworm Castings Grow Up to 3X More Indoor & Outdoor Plants Vegetables Flowers Gardens

Earth Science$23.72108 rev

1y ago

Worm Castings for Plants 1 QT (1.5lbs). Organic Soil Rebuilder and Plant Fertilizer.

Happy Bunny Farms$11.6240 rev

1y ago

Worm Casting Tea Concentrate Liquid Microbial Supplement for Living Soil Stronger Roots & Healthier Plants 8 oz

TPS NUTRIENTS$11.6164 rev

2y ago

Back to the Roots Organic Worm Castings for Plants Natural Fertilizer and Soil Enhancer for Gardening Made in the USA 5lb

Back to the Roots$14.87906 rev

2y ago

What buyers say about worm castings

What buyers praise and complain about, mined from review topics.

What buyers love

Plant Growth42%

“grow so very well”

Quality-Overall27%

“Amazing quality”

Value For Money7%

“Worth it”

Advertised Vs Actual Product5%

“As advertised”

Smell3%

“It's odor free”

Ease Of Use3%

“Easy to use”

Pest/Insect Control2%

“does make a difference with plants add I have found it keeps away white flies”

Moist/Dry1%

“help keep it moist”

Size-Overall1%

“Great quantity, and size for the price”

Strength1%

“Makes things grow faster, bigger and stronger”

What buyers complain about

Quality-Overall13%

“Poor quality control, apparently”

Value For Money12%

“Not an incredible value”

Plant Growth12%

“My vegetables last year grew crazy”

Size-Overall12%

“bag is small”

Smell8%

“The smell is a bit strong”

Moist/Dry4%

“Worse ever dry & crumbly”

Functionality-Overall4%

“bers does not work”

Wood Quality4%

“Has rocks and wood chippings”

Leak-Proof3%

“The bag was leaking”

Contamination3%

“Try not to think about it, and feed this and that Alaskan fish emulsion and other nasty things”

Top return reasons

Value For Money32%

Size-Overall26%

Leak-Proof11%

Smell8%

Advertised Vs Actual Product7%

Functionality-Overall3%

Plant Growth3%

Defective Material/Parts2%

Contamination2%

Quality-Overall2%

Common questions

Is worm castings profitable to sell on Amazon United States?: The niche generates $2.0M/yr across 27 tracked products. 1 of 1 products launched in the last 360 days are still selling. 90-day search growth is +8.3%. Flapen's verdict: Launch it (62/100).
How competitive is the worm castings niche?: 14 brands and 35 sellers compete. The top 5 products take 54% of clicks and top 5 brands hold 83% of demand.
What do buyers complain about in worm castings?: Top complaints mined from reviews: Quality-Overall, Value For Money, Plant Growth. The return rate is 0.2%.
When does demand for worm castings peak?: Demand peaks in Mar–Apr–May; the busiest month runs 3.3× the quietest.
What does it cost to enter the worm castings niche?: Listings span $7.50–$67.40; the average listing price is $22.07 (sweet spot $15–$100). The average incumbent carries 1,936 reviews — the moat a new listing must climb.