Can I Put a Polytunnel on My Allotment?

Introduction

A polytunnel can be a fantastic addition to your allotment, allowing you to extend the growing season, protect crops from harsh weather, and cultivate a wider range of plants. However, before installing a polytunnel, it’s essential to understand the rules, permissions, and considerations specific to allotment sites. This guide covers what you need to know about adding a polytunnel to your allotment, including how to check regulations, choose the right size, and maintain it for optimal use.

1. Check Allotment Rules and Permissions

Different allotments have different policies on structures, so it’s essential to start by reviewing the specific rules for your site.

Review Your Tenancy Agreement

Check Permitted Structures: Your tenancy agreement or allotment association rules often specify which structures are allowed, including any size restrictions or materials permitted for polytunnels.
Approval Requirements: Some allotments require written permission before adding structures like polytunnels. Be sure to follow any outlined approval process to avoid issues.

Consult Your Allotment Association or Council

Ask About Size and Placement Limits: Many councils and allotment associations have specific regulations about the maximum allowable size of polytunnels and where they can be placed.
Application Process for Larger Structures: For larger polytunnels, you may need to submit an application or proposal, detailing dimensions and intended use, before setting it up.

2. Understanding Planning Permission Requirements

In some cases, allotment structures may need planning permission, especially if they are large or semi-permanent.

Permitted Development Rights

General Exemptions: Small garden structures like polytunnels often fall under permitted development and don’t require planning permission. However, this can vary, especially on community allotments.
Consult Local Planning Authority: Contact your local council’s planning department to verify if planning permission is necessary for your polytunnel, particularly if it is over a certain size.

Temporary vs. Permanent Structures

Non-Permanent Foundations: Allotments generally allow only temporary structures, so avoid permanent concrete foundations. Opt for removable bases, like gravel or stakes, to ensure the structure remains temporary.
Wind Protection Considerations: Make sure your polytunnel is secured with removable anchors that can withstand winds without needing a fixed foundation.

3. Choosing the Right Size and Type of Polytunnel

Selecting a polytunnel that fits within allotment guidelines and meets your gardening needs is crucial.

Size Restrictions

Height and Width Limits: Allotments often restrict the height and width of structures to prevent shading on neighboring plots. Common size limits are around 8ft x 10ft for smaller plots, but check with your site.
Space for Crop Rotation: Consider the interior space for crop rotation and maneuvering, but keep within the size guidelines to avoid issues with other plot holders.

Materials and Structure

Polyethylene vs. PVC Covering: Polyethylene is a popular choice for its durability, but some allotments may specify particular materials, so check if your allotment has any preferences.
Reinforced Frame for Stability: Choose a sturdy frame made of galvanized steel or heavy-duty aluminum to withstand weather exposure without warping.

4. Positioning Your Polytunnel on the Allotment

Where you place your polytunnel can impact both crop growth and its stability on the plot.

Sunlight and Shade Considerations

South-Facing Orientation: A south-facing orientation ensures maximum sunlight exposure, which is especially important during winter months for heat retention.
Avoid Shading Neighboring Plots: Position your polytunnel to avoid casting shade on neighboring allotments, as this can lead to complaints or requests for relocation.

Wind Protection

Choose a Sheltered Spot: Locate your polytunnel in a spot that is protected from prevailing winds. Natural windbreaks, like hedges or fences, can help protect the structure.
Secure Anchoring: Use ground anchors, pegs, or sandbags to secure your polytunnel, as strong winds can destabilize lightweight structures.

5. Maintaining Your Polytunnel for Longevity

Regular maintenance will keep your polytunnel in good condition and maximize its effectiveness.

Routine Cleaning

Clean the Covering: Dirt, algae, and debris can reduce light penetration, so clean the covering with mild soapy water every few months to maintain transparency.
Clear Out Weeds and Debris: Keep the interior of the polytunnel weed-free and tidy to prevent pest infestations and disease buildup.

Inspect and Repair

Check for Damage: Regularly inspect the frame and cover for any tears, holes, or loose fittings. Promptly repairing small issues prevents further damage.
Seasonal Adjustments: Reinforce the structure and tighten fittings before winter to withstand strong winds and storms, and consider using a shade cloth in summer to reduce excessive heat.

6. Planning for Optimal Use of the Polytunnel

Maximize your polytunnel’s potential by planning its layout, choosing appropriate crops, and using season-extending techniques.

Organize Efficiently

Install Shelving or Benches: Utilize vertical space with shelving or benches for seedlings, herbs, and compact plants, freeing up ground space for larger crops.
Designate Space for Crop Rotation: Rotate crops within the polytunnel to maintain soil health, especially for heavy feeders like tomatoes and cucumbers.

Choose Suitable Crops

Early and Late Season Crops: Polytunnels allow you to start cool-weather crops early, like lettuce and spinach, and continue growing them late into autumn.
Heat-Loving Plants: Tomatoes, peppers, cucumbers, and melons thrive in the warmth and protection of a polytunnel, producing better yields than they would outdoors.

Ventilation and Temperature Control

Open Vents in Warm Weather: Ventilation reduces humidity and heat, preventing mold and mildew issues. Open doors or windows in summer to maintain airflow.
Add Shade in Summer: Use shade cloth in peak summer to prevent overheating, which can stress plants and reduce yields.

Conclusion

Adding a polytunnel to your allotment is a great way to expand your growing season, protect delicate plants, and create a more controlled environment for crops. However, before setting up a polytunnel, check with your allotment association or local council to ensure compliance with size, placement, and material regulations. By choosing the right size, placing it carefully, and maintaining it regularly, you can enjoy the benefits of a polytunnel on your allotment, cultivating a wider range of crops and extending your gardening year.