Midterm Exam

HORT 2375 - L 10 Lecture 5: Polyethylene Coverings Installation

Steps to Install a Polyethylene Covering

  • Determine Film Type:

    • Decide between single or double polyethylene film.

  • Choose Right Film Based On:

    • Crop light requirements.

    • Number of growing seasons.

    • Prevailing weather conditions.

    • Prevailing light conditions.

    • Structure of the greenhouse.

    • Supply and availability of materials.

    • Consult greenhouse suppliers for advice.

Materials Required for Installation

  • Supplier Responsibilities:

    • Greenhouse supplier should provide all means to install and secure polyethylene.

  • Essential Materials Include:

    • Poly-locks

    • Poly-lock wire

    • Roll-up poly-lock

    • Roll-up hand cranks or motors

    • Inflation kits

    • Air inflation connections

    • Gable ends (polycarbonate or double poly)

Poly-lock Usage

  • Key Features of Poly-locks:

    • Used to secure the edges of polyethylene covering.

Roll-Up Walls

  • Manual vs Automation Options:

    • Manual includes hand cranks.

    • Automated includes 100-watt electric motors for roll-up mechanisms.

Inflation Kits for Installation

  • Purpose:

    • Prevent condensation between two covering films when outside humidity is lower than inside greenhouse humidity.

  • Components:

    • Blower kit for both inside and outside installation.

    • Air connections and jumper hoses for inflation.

Lecture 6: Greenhouse – Inside Layout

Growing on Benches

  • Benefits of Bench Growing:

    • Enhances crop health and circulation of air.

    • Reduces pest and disease issues.

    • Prevents moisture from the ground.

    • Keeps foliage drier than ground growing, mitigating weed issues.

Types of Benches

  1. Stationary Benches

    • Common styles: Longitudinal, peninsular.

    • Features:

      • Easier access to plants.

      • Improved segregation helps in research.

      • Dimensions: 70 cm tall – 1.8 m wide.

  2. Mobile Benches

    • Designed for optimize space usage via rolling benches.

    • Detachable bench tops for easy access but may tip if unevenly loaded.

  3. Container Benches

    • Known as Dutch trays, facilitate handling throughout planting and harvesting.

    • Can roll on tubes or pipes; made from steel or aluminum for durability.

Transport Systems in Greenhouses

  • Automatic Transport Lines:

    • Facilitate movement between rows and connect growing areas to work areas.

  • Overhead Crane Use:

    • Efficient for both empty and filled benches, promoting workspace management.

Growing on the Ground

  • Considerations for Ground Growing:

    • Least costly but challenges like pathogens, airflow, weeds, and moisture levels are present.

  • Cleaning Difficulties:

    • Difficult to sanitize environments and capture runoff.

Conveying Systems

  • Conveyor Types:

    • Portable: Moves containers steadily.

    • Fixed: Used for multiple operations, such as sorting and quality control.

Additional Infrastructure and Layout Considerations

  • Layout Needs:

    • Growth area, storage, shipping, media preparation, and administrative areas.

  • Season Extension Facilities:

    • Cold frames and heated greenhouses for winterizing plant materials.

Environmental and Operational Planning

  • Factors influencing these choices include:

    • Utilities, zoning constraints, and environmental risks.

  • Signage:

    • Clearly displayed across the facility for safety and operational flow.

Conclusion

  • Proper installation and management of polyethylene, along with understanding greenhouse structures and layout, are critical for successful greenhouse operations.