Which is cheaper for lettuce: waxed boxes, wet lock boxes or PP corrugated?

Per single trip, waxed and wet lock corrugated are usually cheapest upfront. But waxed boxes are not recyclable and carry disposal fees of roughly US$0.10–0.20 per box in many US markets, while a PP corrugated box costing about US$1.60–4.00 can run 20–50 trips, bringing cost per trip below US$0.20 and eliminating disposal fees.

What thickness of corrugated plastic is right for lettuce boxes?

For leaf lettuce cartons up to about 11 kg (24 lb) net, 3 mm PP corrugated is usually enough. For 24-count romaine at 16 kg (35 lb) and wrapped iceberg at 20–24 kg (45–52 lb), choose 4 mm; use 5 mm when boxes are iced and stacked more than 8 high in transit.

Leafy Greens Boxes: Lettuce Carton Sizes & Wet-Pack Guide

Q: What size box is used for 24-count romaine lettuce?

A standard 24-count romaine carton measures about 23.25 × 15.38 × 12.00 in (591 × 391 × 305 mm) and holds roughly 35 lb (15.9 kg) net. The footprint is close to the 600 × 400 mm standard, so romaine loads efficiently on 1200 × 1000 mm and 1200 × 800 mm pallets.

Q: Can leafy greens boxes handle ice injection and hydro-cooling?

Only wet-strength packaging survives ice injection: waxed (wax-impregnated) corrugated, wet lock coated corrugated, or PP corrugated plastic. Plain kraft corrugated loses most of its stacking strength when saturated. PP corrugated boxes absorb no water at all, so compression strength is the same wet or dry.

Q: How many lettuce boxes fit in a 40 ft container?

PP corrugated boxes ship flat-packed: a 40HQ container typically carries about 18,000–30,000 flat boxes in the 600 × 400 mm footprint range, depending on height and thickness. Erected boxes for local use load far fewer, which is why most exporters buy flat and erect at the packhouse.

Q: What is the MOQ and lead time for printed leafy greens boxes?

Typical MOQ for custom-printed PP corrugated produce boxes is 1,000–3,000 pieces per size. Samples usually take 5–7 days and production runs 15–20 days plus transit. Fuxing Group produces in China, Vietnam and the Philippines with FDA food-grade PP and up to 8-color printing.

Quick answer

A 24-count leaf lettuce carton is about 495 × 327 × 330 mm and holds 24 lb (10.9 kg); a 24-count romaine carton is about 591 × 391 × 305 mm at 35 lb (15.9 kg); wrapped iceberg ships at 45–52 lb (20–24 kg) per box. Because most leafy greens are hydro-cooled, top-iced or ice-injected, the box must keep its strength when wet — that means waxed corrugated, wet lock boxes, or PP corrugated plastic. A 4 mm PP corrugated box in the same 600 × 400 mm footprint costs roughly US$1.60–4.00 FOB, survives 20–50 trips, and loses zero stacking strength when saturated.

Standard leafy greens carton sizes and weights

The table below shows shipper-grade carton formats used by major US leafy greens growers (specs as published by Duda Farm Fresh Foods, one of the largest leaf producers). Use it to match box footprints before requesting quotes.

Crop / pack	Carton size (in)	Carton size (mm)	Net weight
Green leaf, 24 ct	19.50 × 12.88 × 13.00	495 × 327 × 330	24 lb / 10.9 kg
Red leaf, 24 ct	19.50 × 12.88 × 13.00	495 × 327 × 330	24 lb / 10.9 kg
Leaf lettuce, 12 ct flip-top	19.69 × 13.13 × 7.75	500 × 334 × 197	20–27 lb / 9.1–12.2 kg
Romaine, 24 ct	23.25 × 15.38 × 12.00	591 × 391 × 305	35 lb / 15.9 kg
Romaine, 12 ct	19.69 × 13.13 × 7.75	500 × 334 × 197	25 lb / 11.3 kg
Iceberg, 30 ct	23.19 × 15.19 × 10.38	589 × 386 × 264	44 lb / 20.0 kg
Iceberg, 24 ct wrapped	23.19–23.31 × 15.25–15.50 × 9.38–11.75	≈589 × 388 × 238–298	45–52 lb / 20.4–23.6 kg
Bunched spinach / kale / collards (typical)	≈23 × 15 × 10–12	≈590 × 390 × 250–300	20–25 lb / 9–11.3 kg, often top-iced

Romaine and iceberg footprints (≈590 × 390 mm) are close to the international 600 × 400 mm standard — the most efficient footprint on both 48 × 40 in GMA pallets and 1200 × 1000 mm export pallets.

Why leafy greens need a wet-strength box

Leafy greens are the most water-exposed category in fresh produce logistics. Between harvest and retail a lettuce box typically goes through:

Hydro-cooling or vacuum cooling immediately after harvest — the box gets soaked or condensation forms as the core temperature drops to 1–2 °C.
Top icing or ice injection for spinach, kale, collards and green onions — crushed ice sits directly on the product and melts through transit.
High-humidity cold rooms (95 %+ RH) for the entire cold chain.

Plain kraft corrugated can lose half or more of its compression strength when saturated, which is why the leafy greens trade standardized on three wet-strength options: waxed corrugated, wet lock boxes (curtain-coated, wax-alternative corrugated), and PP corrugated plastic boxes.

Waxed vs wet lock vs PP corrugated for lettuce

Criteria	Waxed corrugated	Wet lock boxes	PP corrugated plastic
Wet compression strength	Good while wax intact	Good; coating can scuff at handholds	Unchanged — PP absorbs no water
Ice injection / top ice	Yes	Yes	Yes, including full immersion
Trips per box	1	1	20–50
Recyclable	No — landfill; disposal fees ≈US$0.10–0.20/box in many US markets	Usually repulpable (check certification)	Yes — 100 % recyclable PP
Washable / food-contact reuse	No	No	Yes, FDA food-grade PP
Typical single-box cost	Low	Low-mid	US$1.60–4.00 FOB (600 × 400 mm class)
Cost per trip at 20+ trips	Full box cost every trip	Full box cost every trip	Often under US$0.20

For a deeper cost model, see our guide Waxed boxes vs corrugated plastic.

Specifying PP corrugated leafy greens boxes

Thickness by load

3 mm — leaf lettuce and bunched greens up to ≈11 kg (24 lb) net.
4 mm — 24-ct romaine (15.9 kg) and iceberg packs (20–24 kg); the workhorse spec for lettuce.
5 mm — iced loads stacked 8+ high, or reusable pool boxes targeting 50 trips.

Full thickness and grammage tables are in the corrugated plastic thickness guide.

Features to request

Drain/vent holes sized so melting ice drains without weakening corner posts.
Interlock tabs for stable mixed-pallet stacking with corrugated cartons.
Up to 8-color printing — brand panels survive water, unlike waxed surfaces.
Flat-pack shipping — approx. 18,000–30,000 boxes per 40HQ in the 600 × 400 mm footprint class.

Commercial terms (typical)

Item	Typical value
MOQ (custom print)	1,000–3,000 pcs per size
Sample lead time	5–7 days
Production lead time	15–20 days + transit
FOB price band (600 × 400 mm class, 3–5 mm)	US$1.60–4.00 per box at volume
Origins	China, Vietnam, Philippines (0% U.S. AD/CVD from the Philippines — not 0% import duty; confirm current Section 301 and HTSUS rates with your broker)

Get a leafy greens box quote in 12 hours

Send your carton size, count and whether the load is iced — we reply with a spec sheet and FOB price. Free samples available.

WhatsApp Quote Email jacky@fuxinggroup.cn

FAQ: Leafy greens shipping boxes

What size box is used for 24-count romaine lettuce?

About 23.25 × 15.38 × 12.00 in (591 × 391 × 305 mm), holding roughly 35 lb (15.9 kg) net. The footprint is close to the 600 × 400 mm standard, so it loads efficiently on GMA and export pallets.

Can leafy greens boxes handle ice injection and hydro-cooling?

Only wet-strength packaging survives: waxed corrugated, wet lock coated corrugated, or PP corrugated plastic. Plain kraft corrugated loses most of its stacking strength when saturated; PP corrugated absorbs no water, so it is equally strong wet or dry.

Which is cheaper for lettuce: waxed, wet lock or PP corrugated?

Waxed and wet lock are cheaper per single trip. A PP corrugated box at US$1.60–4.00 running 20–50 trips drops below US$0.20 per trip and avoids waxed-box disposal fees of roughly US$0.10–0.20 per box.

What thickness of corrugated plastic should lettuce boxes use?

3 mm up to ≈11 kg net, 4 mm for romaine and iceberg packs of 16–24 kg, and 5 mm for iced loads stacked 8 or more high.

How many lettuce boxes fit in a 40 ft container?

Flat-packed, roughly 18,000–30,000 PP corrugated boxes in the 600 × 400 mm footprint class per 40HQ, depending on box height and wall thickness.

What is the MOQ and lead time for printed leafy greens boxes?

Typically 1,000–3,000 pieces per size, samples in 5–7 days, production in 15–20 days. Fuxing Group manufactures FDA food-grade PP corrugated boxes in China, Vietnam and the Philippines with up to 8-color printing.