Use of Biodegradable Mulch for Vegetable Crop

Production

Use of Biodegradable Mulch for Vegetable Crop

Production

M. D. OrzolekDept. of Horticulture

The Pennsylvania State University

M. D. OrzolekDept. of Horticulture

The Pennsylvania State University

Non-degradable plastic film - 1.0 mil

Non-degradable plastic film - 1.0 mil

Different mulch colors-NDDifferent mulch colors-ND

Silver/black on continuous raised beds

Silver/black on continuous raised beds

Retrieved ND plastic film - What to do with it ?

Retrieved ND plastic film - What to do with it ?

ND mulch residue after 10 years applied in the field

ND mulch residue after 10 years applied in the field

Burning plastic mulch in field ??Burning plastic mulch in field ??Polyethylene melts and not incinerates below temps of 1,000 F.Polyethylene melts and not incinerates below temps of 1,000 F.

PlastoFuel – condensed ag plasticsPlastoFuel – condensed ag plastics

PlastoFuelPlastoFuel

PlastoFuel is made by condensing ag and consumer polyethylene and polypropylene plastics. It was developed at Penn State by Garthe Lemont and Orzolek. It was tested in a Korean burner that changed the plastic from a solid to liquid to gas and incinerated @ 2,000°F.

PlastoFuel is made by condensing ag and consumer polyethylene and polypropylene plastics. It was developed at Penn State by Garthe Lemont and Orzolek. It was tested in a Korean burner that changed the plastic from a solid to liquid to gas and incinerated @ 2,000°F.

Burner which incinerated plasticsBurner which incinerated plastics

Degradable PlasticDegradable Plastic

Mid-1970’s British and American scientists discover biodegradable plastic derived from cornstarch.

In 1996, four percent of all plastic production was biodegradable at a cost of $2 to $3/pound compared to $0.50/pound for nondegradable plastic.

Mid-1970’s British and American scientists discover biodegradable plastic derived from cornstarch.

In 1996, four percent of all plastic production was biodegradable at a cost of $2 to $3/pound compared to $0.50/pound for nondegradable plastic.

Photodegradable PlasticPhotodegradable Plastic

Mid 1980’s photodegradable plastic mulch was developed but was very unpredictable in timing of initial degradation. The plastic mulch has to be completely intact for minimally 30 days for crop response.

Mid 1980’s photodegradable plastic mulch was developed but was very unpredictable in timing of initial degradation. The plastic mulch has to be completely intact for minimally 30 days for crop response.

Early plastic degradation prior to crop maturity

Early plastic degradation prior to crop maturity

Biodegradable MulchBiodegradable Mulch

Grower considerations:Degrades in field - no retrievalMultiple colors availableHigher product cost compared to

non-degradable mulchVariable widths available - 3’ to 5’.

Grower considerations:Degrades in field - no retrievalMultiple colors availableHigher product cost compared to

non-degradable mulchVariable widths available - 3’ to 5’.

Trial SpecificsTrial Specifics

Crops:2005/06/07/08Bell pepper,cantaloupe, and

eggplant.

Crops:2005/06/07/08Bell pepper,cantaloupe, and

eggplant.

Field DesignField Design

3 replications12 plants per treatment In-row-spacing 2’ and between row

spacing 6’ to 8’.All crops were established from

locally grown transplants.

3 replications12 plants per treatment In-row-spacing 2’ and between row

spacing 6’ to 8’.All crops were established from

locally grown transplants.

Field Observation -7/22/05

Field Observation -7/22/05

All biodegradable mulch colors were brittle with longitudinal cracks (tears) in plastic. Approximately 10% to 15% of soil visible on raised bed. Currently, few if any weeds in row with crops.

All biodegradable mulch colors were brittle with longitudinal cracks (tears) in plastic. Approximately 10% to 15% of soil visible on raised bed. Currently, few if any weeds in row with crops.

Longitudinal tear in mulchLongitudinal tear in mulchMulch may tear during application in the field.Mulch may tear during application in the field.

Degradation of mulch along soil lineDegradation of mulch along soil lineBiodegradable mulch will initially degrade along soil line on shoulder of bed.Biodegradable mulch will initially degrade along soil line on shoulder of bed.

Field Observation -10/20/05

Field Observation -10/20/05

Retrieved non-degradable black and blue plastic mulch and drip tape from field. Biodegradable mulch colors were approximately50% to 60% degraded.

Retrieved non-degradable black and blue plastic mulch and drip tape from field. Biodegradable mulch colors were approximately50% to 60% degraded.

Biodegradable MulchBiodegradable Mulch

Field Observation - 7/12/06

Field Observation - 7/12/06

The brown BD mulch appeared to be degrading faster than either the black or green BD. Less mulch breakdown with melon crop compared with pepper crop. No difference in crop growth between non-degradable and biodegradable plastic mulches.

The brown BD mulch appeared to be degrading faster than either the black or green BD. Less mulch breakdown with melon crop compared with pepper crop. No difference in crop growth between non-degradable and biodegradable plastic mulches.

Field Observation - 8/24/06

Field Observation - 8/24/06

On the average, 30% to 50% of soil was visible in beds where BD mulch had degraded. Significant weed growth observed in row when soil was not covered with plastic mulch.

On the average, 30% to 50% of soil was visible in beds where BD mulch had degraded. Significant weed growth observed in row when soil was not covered with plastic mulch.

2005 Marketable Pepper Yield

2005 Marketable Pepper Yield

Mulch type # fruit Wt. fruit-lbs.

Avg.fruit wt. - oz.

ND black 30.0 11.9 6.3

ND blue 9.0 2.6 4.6

BD black 39.7 12.8 5.2

BD brown 44.3 14.5 5.2

BD green 29.0 9.5 5.2

2006 MarketablePepper Yield

2006 MarketablePepper Yield

Mulch type

# Fruit Wt. fruit lbs.

Avg. fruit wt. - oz.

ND black 38.7 18.4 7.6

ND IRT 22.0 9.4 6.8

BD black 24.7 10.5 6.8

BD brown 25.0 11.7 7.5

BD green 31.7 13.9 7.0

2007 Marketable Pepper Yield

2007 Marketable Pepper Yield

Treatment # of fruit Wt. fruit lbs.

Avg. fruit wt. (oz)

No plastic 47.3 18.8 6.3

ND film 96.0 38.9 6.5

BD film - thin

73.3 31.0 6.8

BD film - thick

74.3 31.36.7

2008 Pepper Trial2008 Pepper Trial

Mulch # Fruit Wt. - lbs. #/plant

MTX#25 93.7 36.0 7.8

ND poly 107.3 41.1 8.9

Biotelo 86.0 30.3 7.2

MTX#35 108.0 39.9 9.0

MTX#32 97.0 36.7 8.1

Bare soil 57.0 15.9 4.8

2005 Marketable Melon Yield

2005 Marketable Melon Yield

Mulch type

# Fruit Wt. fruitLbs.

Avg. fruitWt. - lbs.

ND black 19.3 53.6 2.8

ND blue 20.0 64.6 3.2

BD black 20.0 68.3 3.4

BD brown 13.7 44.6 3.3

BD green 16.7 43.8 2.6

2006 MarketableMelon Yield

2006 MarketableMelon Yield

Mulch type

# Fruit Wt. fruitLbs.

Avg.fruitWt. - lbs.

ND black 18.3 76.9 4.2

ND IRT 25.3 79.0 3.1

BD black 16.7 56.0 3.4

BD brown 18.7 64.2 3.4

BD green 17.3 42.3 2.4

2008 Melon trial2008 Melon trial

Mulch #fruit Wt. - lbs. Avg.wt

MTX#25 17.3 58.7 3.4

ND poly 21.0 92.3 4.4

Biotelo 15.0 74.9 5.0

MTX#35 17.0 75.1 4.4

MTX#32 13.3 41.1 3.1

Bare soil 11.0 42.4 3.9

2008 Field Trials2008 Field Trials

2008 Field Trials2008 Field Trials

2008 Field Trials2008 Field Trials

2008 Eggplant Trial2008 Eggplant Trial

Mulch #fruit Wt.-lbs. #/plant

MTX#25 51.0 38.0 6.4

ND poly 68.0 48.0 8.5

Biotelo 46.7 34.9 5.8

MTX#35 48.7 36.2 6.1

MTX#32 59.0 40.8 7.4

Bare soil 18.0 12.6 2.3

Soil Temp - 7/14 at 1:00pm - 2” below soil

Soil Temp - 7/14 at 1:00pm - 2” below soil

Mulch Temp-°F

MTX#25 97.5

ND poly 93.8

Biotelo 91.1

MTX#35 98.8

MTX#32 97.9

Bare soil 80.4

Conclusions from studyConclusions from study

Yield of both pepper and cucurbit fruit from plants grown on biodegradable plastic mulch is equal to or sometimes higher compared to pepper and cucurbit crops grown on non-degradable plastic mulch.

Yield of both pepper and cucurbit fruit from plants grown on biodegradable plastic mulch is equal to or sometimes higher compared to pepper and cucurbit crops grown on non-degradable plastic mulch.

Conclusions from studyConclusions from study

Biodegradable (BD) plastic mulch does not have to be retrieved from field, but can be incorporated with a rototiller or disk in the fall.

It appears that BD mulch will start to degrade about 45 to 50 days after laying the mulch in the field.

Biodegradable (BD) plastic mulch does not have to be retrieved from field, but can be incorporated with a rototiller or disk in the fall.

It appears that BD mulch will start to degrade about 45 to 50 days after laying the mulch in the field.

Incorporating biodegradable plastic mulch-9/23/08

Incorporating biodegradable plastic mulch-9/23/08

Conclusion from studyConclusion from study

Response of various vegetables to mulch color similar in both non-degradable and biodegradable plastic mulch.

Response of various vegetables to mulch color similar in both non-degradable and biodegradable plastic mulch.

Conclusions from studyConclusions from study

Under dry or drought conditions, the rate of degradation of BD plastic mulch is slower compared to growing seasons with weekly rainfall.

If BD mulch degrades earlier than 45 days, weed populations may be very competitive with crop - exception 2008 field study.

Under dry or drought conditions, the rate of degradation of BD plastic mulch is slower compared to growing seasons with weekly rainfall.

If BD mulch degrades earlier than 45 days, weed populations may be very competitive with crop - exception 2008 field study.

Grower considerations with BD mulch

Grower considerations with BD mulch

Initial cost of roll of BD plastic mulch about 50% higher than ND mulch.

Currently, rolls of BD mulch available in 3, 4,or 5 foot widths.

Initial cost of roll of BD plastic mulch about 50% higher than ND mulch.

Currently, rolls of BD mulch available in 3, 4,or 5 foot widths.

Any questions?Any questions?

from audiencefrom audience