Is worm castings profitable to sell on Amazon United Kingdom?

The niche generates £29K/yr across 14 tracked products. 0 of 4 products launched in the last 360 days are still selling. 90-day search growth is +1.9%. Flapen's verdict: Skip it (40/100).

How competitive is the worm castings niche?

7 brands and 7 sellers compete. The top 5 products take 68% of clicks and top 5 brands hold 92% of demand.

What do buyers complain about in worm castings?

Top complaints mined from reviews: Size-Overall, Value For Money, Ease Of Use. The return rate is 0.1%.

When does demand for worm castings peak?

Demand peaks in Mar–Apr–May; the busiest month runs 3.1× the quietest.

What does it cost to enter the worm castings niche?

Listings span £4.94–£16.48; the average listing price is £9.33 (sweet spot $15–$100). The average incumbent carries 235 reviews — the moat a new listing must climb.

worm castings

Skip it

A small market ($29K/yr) — this niche doesn't clear our bar today.

Returns

Incredible0.1%

return rate — above 5% kills the launch gate

Review moat

Great235.29

avg incumbent reviews — the moat a new listing must climb

Conversion

Good5.6%

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

Quality gap

Good4.4★

avg incumbent rating — lower means beatable quality

Competition

Okay68%

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

Avg price

Okay£9.33

avg listing price — sweet spot $15–$100

Growth

Okay+1.9%

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

Brand share

Bad92%

top-5 brand share — brand-locked demand

Price range

Bad£4.94–£16.48

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

Market size

Bad£29K

£29K/yr · 56K searches

Signals Low Review Barrier

According to Flapen's Amazon United Kingdom niche tracking, worm castings is a £29K/yr Amazon United Kingdom market (56K searches/yr). The top 5 brands hold 92% of demand. Demand peaks in Mar–Apr–May. Verdict: Skip it — 40/100.

Data updated Jul 26, 2026 · scored weekly · How we score niches

worm castings market data

Units sold / yr: 3K–3K; avg 100–250/product
Revenue / yr: £23K–£28K; units × avg price
Conversion rate: 5.6%
Avg BSR: #314
Page quality: 0%
Prime: 64%
Sponsored: 64%
Out of stock: 7.7%
Avg brand age: 58 months
Avg seller age: 192 days

Competition & brand share

The top 5 products take 68% of clicks — established leaders, but buyers still shop beyond them.

Brands

7 flat

Sellers

Top-5 brand share

92%

Top 20: 100%

Top-5 click share

68%

Top 20: 100%

Open market

Growcery32%
Baltic Worm23%
Invigortex21%
Generic10%
R&R SHOP6%
Elixir Gardens5%
Open — no brand owns it (1 brand, 3%)

Demand & seasonality

Weekly Amazon search volume, last 64 weeks — +1.9% search growth over the last 90 days.

Peak months: Mar, Apr, May · busiest ÷ quietest = 3.1×

Open Trend

Top worm castings search terms

worm castings42K/yr -1.1%4.3% conv.
worm castings for plants11K/yr +3.9%4.4% conv.
vermicompost3K/yr +38.1%0.9% 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 14 tracked products in this niche — three views at once, no toggling.

Top sellers

by 90-day click share

Growcery Worm Castings - Premium Fertiliser for Plants Superior Soil Improver UK and Rich Vermicompost for Enhanced Plant Health and Vigour Fertiliser for plants outdoor and indoor (1L)

Growcery£6.684.6★96 rev

Black Gold Worm Castings 100% Organic Microbe-Rich Fertiliser Improves Soil Retains Moisture & Boosts Growth For Houseplants Gardens & Lawns (5 Litre)

Invigortex£11.934.1★43 rev

Worm Castings Pure Natural Multipurpose Fertilizer for Indoor and Outdoor Plants Vermicompost TopSoil Builder Improver Plant & Root Growth Feed Fertiliser for Potting Germination NPK Nutrient

Baltic Worm£10.634.5★463 rev

Baltic Worm Worm Castings 5 Liter - Pure Multipurpose Fertiliser Vermicompost - Natural Top Soil Builder and Improver Plant Feed for Potting Germination Growing

Baltic Worm£16.484.6★1,245 rev

Plantalaya Worm Castings Organic Soil Booster & Natural Plant Food Premium Earthworm Casting Nutrient Rich Soil Improver (0.5 Litre)

Generic£5.864.2★3 rev

Newest

by launch date

Plantalaya Worm Castings Organic Soil Booster & Natural Plant Food Premium Earthworm Casting Nutrient Rich Soil Improver (0.5 Litre)

Generic£5.863 rev

2mo ago

Growcery Living Soil Mix with Mycorrhizal Fungi Worm Castings & Activated Biochar Bioactive Potting Soil for Houseplants & Garden Plants (1L)

Growcery£6.6238 rev

4mo ago

Black Gold Worm Castings Bucket | 100% Worm Castings for Mixing or Topdressing | Pots Gardens & Raised Beds | Supports Microbial Activity & Root Health (10L)

Invigortex£13.2911 rev

9mo ago

Black Gold Worm Castings 100% Organic Microbe-Rich Fertiliser Improves Soil Retains Moisture & Boosts Growth For Houseplants Gardens & Lawns (5 Litre)

Invigortex£11.9343 rev

10mo ago

Growcery Worm Castings - Premium Fertiliser for Plants Superior Soil Improver UK and Rich Vermicompost for Enhanced Plant Health and Vigour Fertiliser for plants outdoor and indoor (1L)

Growcery£6.6896 rev

2y ago

What buyers say about worm castings

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

What buyers love

Quality-Overall49%

“good quality”

Plant Growth31%

“They are growing healthy”

Value For Money7%

“Good value for money”

Advertised Vs Actual Product4%

“does the job”

Smell2%

“Something really good is that doesn't smell compare with other similar products”

What buyers complain about

Size-Overall36%

“Its to small”

Value For Money21%

“Expensive”

Ease Of Use14%

“It was too stressful to deal with it so I just threw away the leftover after a couple of use”

Quality-Overall14%

“yellow balls rubbish quality”

Top return reasons

Value For Money43%

Functionality-Overall14%

Advertised Vs Actual Product14%

Size-Overall14%

Defective Material/Parts14%

Common questions

Is worm castings profitable to sell on Amazon United Kingdom?: The niche generates £29K/yr across 14 tracked products. 0 of 4 products launched in the last 360 days are still selling. 90-day search growth is +1.9%. Flapen's verdict: Skip it (40/100).
How competitive is the worm castings niche?: 7 brands and 7 sellers compete. The top 5 products take 68% of clicks and top 5 brands hold 92% of demand.
What do buyers complain about in worm castings?: Top complaints mined from reviews: Size-Overall, Value For Money, Ease Of Use. The return rate is 0.1%.
When does demand for worm castings peak?: Demand peaks in Mar–Apr–May; the busiest month runs 3.1× the quietest.
What does it cost to enter the worm castings niche?: Listings span £4.94–£16.48; the average listing price is £9.33 (sweet spot $15–$100). The average incumbent carries 235 reviews — the moat a new listing must climb.