Abstract
De-inked paper sludge from newsprint recycling was evaluated as an alternative amendment in bedding plant production. `Sweet Dreams' geranium ( Pelargonium × hortorum ) and `Crystal White' zinnia ( Zinnia angustifolia ) were grown in square 10-cm pots in one of five media. Media contained 0%, 20%, 40%, 60%, or 80% de-inked paper sludge by volume. All mixes contained 10% perlite, and peatmoss was used to bring the volume to 100%. Initial chemical and physical characteristics of the media were determined. Plants were grown in a greenhouse for 8 weeks, and then plant height, shoot dry weight, and average plant width were determined. Media containing 20% or less paper sludge had an average pH of 4.4, whereas those containing more sludge had an average pH of 7.0. Cation exchange capacity of the media decreased significantly as the volume of sludge increased. Media containing 60% or more paper sludge were better aerated, but held less water than those made with 40% or less de-inked sludge. Geraniums grown in 20% or less paper sludge were at least 18% taller than those grown in medium containing 40% or more de-inked sludge, but average dry weights and plant widths of these plants were unaffected by the media. Zinnia plants grown in 20% or less paper sludge produced four times more shoot dry weight and were at least 34% taller and 20% wider than those grown in 40% or more sludge. Overall, zinnias grown in 40% or more sludge were unacceptable for commercial sale. A volume of 20% de-inked paper sludge could safely be included in potting media used for production of `Sweet Dreams' geranium and `Crystal White' zinnia.
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Claims 8
Claim · model-written summary
Geraniums in at most 20% sludge were at least 18% taller than those in at least 40%.
- Treatment
- 20% or less paper sludgee0
- Outcome
- tallere0
- Direction
- tallere0
- Value
- 18%e0
- Comparator
- 40% or more de-inked sludgee0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.

Verbatim
e0“Geraniums grown in 20% or less paper sludge were at least 18% taller than those grown in medium containing 40% or more de-inked sludge”
Claim · model-written summary
Geranium dry weight and width were unaffected by sludge media.
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.

Verbatim
e0“average dry weights and plant widths of these plants were unaffected by the media”
t0“Geranium”
Claim · model-written summary
Zinnia in at most 20% sludge produced four times the shoot dry weight of those in at least 40%.
- Treatment
- 20% or less paper sludgee0
- Outcome
- shoot dry weighte0
- Direction
- moree0
- Value
- four timese0
- Comparator
- 40% or more sludgee0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.

Verbatim
e0“Zinnia plants grown in 20% or less paper sludge produced four times more shoot dry weight and were at least 34% taller and 20% wider than those grown in 40% or more sludge.”
Claim · model-written summary
Zinnia in at most 20% sludge were at least 34% taller.
- Treatment
- 20% or less paper sludgee0
- Outcome
- tallere0
- Direction
- tallere0
- Value
- 34%e0
- Comparator
- 40% or more sludgee0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.

Verbatim
e0“Zinnia plants grown in 20% or less paper sludge produced four times more shoot dry weight and were at least 34% taller and 20% wider than those grown in 40% or more sludge.”
Claim · model-written summary
Zinnia in at most 20% sludge were at least 20% wider.
- Treatment
- 20% or less paper sludgee0
- Outcome
- widere0
- Direction
- widere0
- Value
- 20%e0
- Comparator
- 40% or more sludgee0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.

Verbatim
e0“Zinnia plants grown in 20% or less paper sludge produced four times more shoot dry weight and were at least 34% taller and 20% wider than those grown in 40% or more sludge.”
Claim · model-written summary
Zinnias in at least 40% sludge were unacceptable for commercial sale.
Organisms pictured · Representative pictures of the matched species, not figures from the paper.

Verbatim
e0“zinnias grown in 40% or more sludge were unacceptable for commercial sale”
Claim · model-written summary
The authors concluded that 20% paper sludge can be used safely for Sweet Dreams geranium.
- Material
- `Sweet Dreams'e0
- Outcome
- 20% de-inked paper sludge could safely be included in potting mediae0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.

Verbatim
e0“A volume of 20% de-inked paper sludge could safely be included in potting media used for production of `Sweet Dreams' geranium and `Crystal White' zinnia.”
Claim · model-written summary
The authors concluded that 20% paper sludge can be used safely for Crystal White zinnia.
- Material
- `Crystal White'e0
- Outcome
- 20% de-inked paper sludge could safely be included in potting mediae0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.

Verbatim
e0“A volume of 20% de-inked paper sludge could safely be included in potting media used for production of `Sweet Dreams' geranium and `Crystal White' zinnia.”
The same questions in other papers
in vitro · growth · GeraniumPositive and negative results
1 paper in the same direction as this paper · 4 in the opposite direction
- positive
- positive
- positive
2 papers more in this group
See all 6 papers →organic · growth · ZinniaResults agree
1 paper in the same direction as this paper
- positive
Claims are grouped by organism, treatment and what was measured or targeted. A paper counts as positive when any of its claims in the group is positive.