Eco-Friendly Small-Pet Bedding: Paper, Hemp, and Aspen Compared

This guide covers what lines the floor of a small-pet enclosure — bedding for the living space generally, not the litter-tray material itself. For litter specifically, see our compostable small-pet litter guide, which focuses on rabbits. This guide is organized by species, since housing needs differ enough between rabbits, guinea pigs, hamsters, and gerbils that a single material comparison doesn't hold up well across all four.

Quick answer: recycled or pulped paper is the most widely recommended eco-friendly bedding for small pets. Hemp is a promising low-dust, highly absorbent alternative, though most research on it so far comes from livestock and laboratory settings. Kiln-dried aspen is the safe wood option. Avoid cedar, raw pine, sawdust, and clumping clay cat litter.

Eco-friendly bedding materials compared

Paper. The Rabbit Welfare Association & Fund describes pulped paper as safe, highly absorbent, and dust-extracted, with good environmental credentials because it's a paper-industry waste product. It notes that paper pellets are very absorbent and good for litter areas, but less comfortable as bedding unless covered with something softer, and that printed or shredded newspaper can be a concern if rabbits eat the ink (RWAF — Bedding and litter).

Hemp. In a study of ten hemp varieties tested as animal bedding, hemp shives absorbed on average about 252% of their weight in water and about 50% ammonia, which the authors describe as similar to commercial bedding like wood shavings. They also note that further on-farm trials are needed for a full assessment (Physical Characterization of Ten Hemp Varieties to Use as Animal Bedding Material). A laboratory-animal study presented at the 2023 AALAS meeting found hemp bedding samples met specifications for moisture, dust, and microbial screening, comparable to hardwood bedding, but also flagged high endotoxin levels and called for more testing (AALAS 2023 abstracts, P424). In short: promising, low-dust, and absorbent, but less studied in home pets than paper.

Straw. For outdoor rabbits, the RWAF recommends good-quality soft straw as warm bedding, chosen dust-extracted and sweet-smelling to minimize eye injury risk. Straw is bedding; hay is food, and rabbits still need plenty of fresh hay to eat (RWAF — Bedding and litter).

Fleece. A reusable fleece setup lets urine pass through to an absorbent layer underneath. A guinea pig rescue's bedding guide notes it means sweeping droppings and hay off daily and washing the fleece roughly every three to five days (MGPR — Bedding for Guinea Pigs). Fleece doesn't suit burrowing species like hamsters and gerbils, which need deep loose bedding.

Rabbit housing

For rabbits, Merck Veterinary Manual's housing guidance — aimed at research and larger-scale settings, though the underlying material properties apply at home too — recommends bedding pens with straw or shredded paper for absorbency, and specifically advises against shavings or sawdust, since they generate dust that can irritate the respiratory tract (Merck Veterinary Manual — Housing of Rabbits). The same source states that adequate ventilation is important at all times, and that excess manure buildup leads to ammonia levels that can predispose indoor rabbits to respiratory disease — frequent manure removal is described as essential.

This guidance is specific to rabbits; it isn't extended to guinea pigs, hamsters, or gerbils below.

Guinea pig housing

Merck Veterinary Manual advises against cedar and raw pine for guinea pigs specifically, because they contain oils that can irritate the lungs (Merck Veterinary Manual — Guinea Pigs). Purdue University's veterinary hospital care sheet confirms cedar should be avoided, citing chronic upper respiratory problems in the studies it references, and extends the same concern to pine (Purdue University College of Veterinary Medicine).

The same Purdue source describes aspen as a non-aromatic hardwood that makes safe bedding, but notes it doesn't control odor well on its own, so strict cage cleaning is needed to manage smell. It also specifically warns against large glass aquariums as guinea pig housing, since they're hard to clean and allow very little air circulation, which lets ammonia levels build up quickly. Timothy hay is described as a workable bedding option, with the caveat that it doesn't control odor and will mold if it gets wet.

This guidance is specific to guinea pigs and is not extended to rabbits, hamsters, or gerbils here.

Hamster and gerbil bedding depth

Hamsters and gerbils are both natural burrowers, and the depth guidance below reflects that. Merck Veterinary Manual recommends at least 6-8 inches (about 15-20 cm) of bedding depth for hamsters, describing a deep-bedding setup as similar to the underground homes hamsters use in the wild (Merck Veterinary Manual — Hamsters). For gerbils, Merck recommends filling the cage about a third deep with bedding, specifically to give them room to dig and hoard food, noting that gerbils build elaborate burrows in the wild (Merck Veterinary Manual — Gerbils).

We don't have a comparable sourced depth recommendation for rabbits or guinea pigs, so none is given here for those species.

Cleaning and air quality

The cleaning and air-quality guidance above is specific to each source. Merck's rabbit housing page ties ammonia buildup to insufficient manure removal and recommends adequate ventilation at all times, without giving a specific cleaning schedule. Purdue's guinea pig care sheet ties ammonia buildup specifically to poor ventilation, such as a glass aquarium enclosure, rather than to a cleaning schedule. Neither the hamster nor gerbil Merck pages address cleaning frequency or ammonia directly, so no claim is made for those two species here.

For the fuller annual habitat reset beyond routine spot-cleaning, see our once-a-year deep clean checklist. Where you place the enclosure in the first place affects how much of this ventilation question you're managing — see our enclosure placement checklist for species-specific guidance on temperature, drafts, and airflow.

FAQ

Is hemp bedding safe for small animals? Hemp is generally considered a low-dust, absorbent option, and lab testing has found it comparable to hardwood bedding on dust and moisture. Most published research comes from livestock and laboratory settings rather than pet homes, and one lab study noted high endotoxin levels (AALAS 2023 abstracts). Choose a dust-extracted product sold for small animals, and watch for sneezing or eye irritation when you switch.

What is the most eco-friendly bedding for small pets? Pulped or recycled paper made from industry waste is a strong all-round choice (RWAF). Hemp and straw are agricultural by-products, and fleece cuts waste because it's reusable. The best choice depends on species: burrowers need deep loose bedding, while guinea pigs can do well on fleece.

Is cedar or pine bedding safe for any small pet? Not for guinea pigs — Merck and Purdue both advise against cedar and raw pine for guinea pigs specifically, due to lung-irritating oils. We don't have the same species-specific guidance confirmed for rabbits, hamsters, or gerbils, so we can't extend this claim to them directly (Merck — Guinea Pigs; Purdue).

How deep should hamster or gerbil bedding be? Merck recommends at least 6-8 inches for hamsters and filling the cage about a third deep for gerbils, since both species burrow (Merck — Hamsters; Merck — Gerbils).

Can I use a glass aquarium for a guinea pig? Purdue's veterinary care guidance specifically advises against it, since aquariums are difficult to clean and allow very little air circulation, letting ammonia build up quickly (Purdue University College of Veterinary Medicine).

Is timothy hay a good bedding choice? For guinea pigs, Purdue describes it as workable but notes it doesn't control odor and will mold if it gets wet (Purdue University College of Veterinary Medicine). We don't have the same guidance for the other three species covered in this guide.

For related small-pet housing topics, see our sustainable rabbit hutch guide and our compostable small-pet litter guide — the litter guide focuses on rabbits specifically. For more small-pet care guides, see our Small Pets Care hub.