BMP testingMunicipal and green waste, paper and textiles

Flower wastes (cut flowers, flower pomace) — BMP: 2 studies, weighted mean 322 m³ CH₄/t VS

Flower waste means pressed flower residues and cutting waste, e.g. gerbera; records from different studies show how varied this stream is.

rating: good CH₄ ≈ 54 % (estimate)

Published 10 September 2026Updated 29 October 20263 min readFeedstockData Editorial Team

Illustration: FeedstockData (AI, Google Gemini)

Weighted mean: 322m³ CH₄/t VS
Range: 281–362m³ CH₄/t VS
Records: 2studies
Publications: 2sources
Temperatures: 38 °Cof the test

Methane in biogas

≈53–56% CH₄

Medium methane content · ≈ 5.4 kWh/m³ of biogas

estimate from the substrate type The collected studies contain no measurement. The interval follows from the approximate composition (protein from total nitrogen (N 2.2 % DM × 6.25)) and the yields of compound groups according to FNR.

How we calculate it and what the zones mean

Rating for biogas plants

good — editorial rating for biogas plantsStable, usually accepted without a fee

Potential per tonne of fresh matter: very high (127 m³ CH₄/t); process risk: inhibitors. Handling costs: physical contaminants (packaging, plastics).

Why? Rating factors

Potential per tonne +3

+3potential 127 m³ CH₄/t fresh matter (BMP 322 × DM 47.1 % × VS 84 %)

Process stability −1

−1inhibitors: natural or residues (e.g. limonene, polyphenols, antibiotics, metals)

Handling and costs −1

−1physical contaminants (packaging, plastics) — depackaging and separation

Total points: 1 · thresholds: ≥ 2.5 very good, ≥ 1 good, below — neutral; negative with cumulative process risk.

Editorial rating per the methodology · confidence of the rating: low · excluding market prices

Add to the co-digestion calculator CSV data

BMP curves from 2 studies

Weighted mean Individual records

Dashed lines are a model curve (first-order kinetics, B(t) = B₀·(1 − e^−kt)); the end point comes from the publication. All curves are model curves.

Cumulative methane production over the test [m³ CH₄/t VS]. The thick line is the weighted mean of all records (322); dots mark the end values given in the publications. Point at the chart to read values; click a legend item to hide or show a record.

Records and sources

Download CSV

Source	BMP m³ CH₄/t VS	Temperature	Sample	Curve
Lallement et al. (2023) DOI	281	38 °C · mesophilic	flower residue pomace	end point (model curve)
Nogueira et al. (2026) DOI	362	—	Gerbera flower residues (FR), mono-digestion	end point (model curve)
Weighted mean	322	arithmetic mean 322, SD 58

Typical composition

Dry matter (DM): 47.1% (range 47.1–47.1)
Volatile solids (VS): 84 % DM (range 84–84)
Nitrogen: 2.2 % DM
C/N ratio: 17.4

Median and range of the determinations reported in the publications behind this substrate's BMP records (read from: MY-D); dry matter: 1 determination, volatile solids: 1 determination. C/N was calculated as the ratio of C and N content (% DM) from the same source. DM from a single determination – indicative value.

Sources: Lallement et al. (2023).

The composition of the raw material varies between batches — for plant calculations use an analysis of your own sample. The calculator inserts typical values automatically.

Process properties

seasonal
contains inhibitors
physical contaminants
variable composition
editorial classification

Low confidence: the description is based on general characteristics of the substrate group, not on studies of this material. Treat it as a hint to be verified.

Advantages

Methane potential in the Substraty.pl BMP dataset: weighted mean 321.8 m³ CH₄/t VS (SD 57.6; 2 records, 2 sources).
Petals and green parts are readily degradable (Weiland 2010).

Drawbacks and risks

Secondary compounds (essential oils, dyes) and plant protection products may inhibit (Chen et al. 2008).
Admixtures of foil, wire and floral foam.

Co-digestion — what to combine it with, what to watch out for

combines well
substrates: high alkalinity (buffer) — e.g. Cattle manure, Pig slurry, Cattle slurry, Duck slurry, Rumen and digestive tract content
Slurry supplies N, alkalinity and trace elements.^[1][2]

Dosing

No source threshold.

Introduce gradually, starting with a small dose and monitoring the process (e.g. FOS/TAC, pH, gas composition).

Practical requirements

Remove foreign contaminants before dosing: material from biowaste may contain interfering substances, and the co-substrate should be free of them (FNR 2010, Ch. 3).

Sources of the process data

The co-digestion calculator will assess a specific mixture containing this substrate.

What it is and where it comes from

Flower waste arises in florists' shops, wholesale markets, cut-flower plantations and in industry using flowers (e.g. pressed residues after extraction). The dataset includes pressed flower residues and gerbera cutting waste. It is a dispersed and seasonal stream, with peaks around holidays.

Properties relevant to digestion

Petals and green parts are rich in water and readily degradable carbohydrates, whereas stems and woody fragments contain lignin. Flowers also contain secondary compounds (essential oils, pigments), which at large doses can inhibit microorganisms. Residues of pesticides and preservatives used in trade are often present, and the waste is sometimes mixed with film, wire or floral foam, which requires sorting.

How to read the spread of results

The records concern two completely different materials, so the dataset does not describe a single characteristic of "flower waste". The flower species, the share of stems, the degree of comminution, industrial processing (e.g. pressing) and test conditions all have an effect. One result comes from a review paper, the other from a study on mono-digestion of gerbera waste.

In biogas plant practice

Flower waste, where available, is used as an addition to a mix with slurry or biowaste. It is necessary to clean it of packaging and inorganic elements and to shred the stems. Because of the variable composition of batches, it is worth carrying out BMP tests periodically. Waste from trade is waste within the meaning of the Waste Act, so the installation must have a permit to accept it.

It should also be taken into account that flower waste is available irregularly, with distinct seasonal peaks, so it is hard to plan a steady share in the feed with it. Its value lies rather in managing a waste that would otherwise go to a composting plant than in supplying a significant part of the installation's energy. With the first deliveries it is good to carry out a BMP test and assess the content of contaminants.

Methodology in brief

BMP is the amount of methane obtained from volatile solids (VS) in a batch test, given in m³ CH₄ per tonne of VS (numerically the same as NmL CH₄/g VS in the publications) and converted to normal conditions (0 °C, 101.325 kPa). The weighted mean gives each publication a total weight of 1, split equally between its results for the substrate — a paper testing twenty varieties does not outweigh a paper with a single sample. In inter-laboratory programmes the unit is the laboratory (total weight 1), and within it the weight of a test grows with the number of bottles (replicates). Results after pretreatment (e.g. thermal, chemical, enzymatic) are shown separately and are not included in the mean.

Solid lines are curves measured in the tests. Where a publication gives only the final result, we draw a first-order kinetic model, B(t) = B₀·(1 − e^−kt): only the end point comes from the publication, and the shape of the curve serves purely as visualisation — do not read the production on a particular day from it. For this substrate k = 0.110 d⁻¹ was assumed (median of rate constants k reported in the sources and/or fitted to the mean measured curves).

The statistics describe the spread of published results — a descriptive compilation, not a meta-analysis or a guarantee of plant yield.

Full methodology and correction policy

Bibliography

All sources of the site: bibliography.