• More Affordable – Costs significantly less than a greenhouse.
• Easier to Install – No need for a foundation, can be set up quickly.
• Better Light Diffusion – Reduces hotspots, leading to healthier plants.
• More Flexible & Durable – Can withstand impacts better than glass.
• Adaptable to Different Climates – Handles extreme weather better.
• Expandable – Easier to extend or modify as your growing needs change.

The Haygrove Garden Tunnel uses the same quality grade steel materials that are used for our commercial field scale polytunnels that are generally built in the hectare. This increases the structural integrity of the Polytunnel in order to withstand unexpended weather events.

Haygrove Garden Tunnels are built with E320 structural-grade steel, the same material used in construction, ensuring superior wind resistance.

Unlike cheaper alternatives that use mild steel, our tunnels are also galvanised providing long-lasting rust protection.

Every Haygrove Garden Tunnel comes with a manual roll-up, roll-down ventilation system, allowing growers to control airflow and temperature with ease.

The vents are covered with an insect-proof net, ensuring optimal air circulation while keeping pests out—reducing the need for chemical pest control.

Absolutely! A common misconception about polytunnels is that they lack sturdiness, but Haygrove Garden Tunnels are engineered for strength, durability, and long-term performance. With over 30 years of expertise in polytunnel design, our engineers have developed a highly robust structure using premium-grade materials.

Each tunnel is built with fully galvanised steel for superior corrosion resistance, and the polythene cover is a unique woven material, offering exceptional durability against wind, rain, and UV exposure.

In every 2-meter section, four reinforced steel anchors secure the structure firmly into the ground. These anchors:

• Are driven at a 45° angle for maximum stability
• Measure 0.8m (2’6″) in length
• Are made from 3mm thick galvanised steel

This design ensures that Haygrove Garden Tunnels withstand harsh weather conditions while remaining a long-term investment for growers.

Yes! Unlike many traditional structures, polytunnels can be erected on slightly uneven surfaces, making them ideal for gardens with sloped or uneven terrain.

Haygrove Garden Tunnels offer greater flexibility in placement and can be installed on gently sloping land without the need for costly groundwork. 

There is no need to level or pave the ground first, making installation quick, simple, and hassle-free.

Properly Ventilated Polytunnel (40°C Outside)

• Shade effect – The polytunnel cover diffuses light, reducing the risk of leaf scorch and fruit sunburn.
• Controlled ventilation – Rolling up the sides increases airflow, preventing extreme temperature spikes.
• Higher humidity retention – Slower water evaporation keeps plants hydrated longer.
• More consistent growing conditions – Less temperature fluctuation between day and night, reducing plant stress.
• Pollen viability improves – Less exposure to extreme direct heat improves fruit set in tomatoes, zucchinis, and beans.

• Warmer internal temperatures – A polytunnel stays 3-5°C warmer than outside, preventing frost from forming.
• Retains soil warmth – The covered environment reduces heat loss from the soil, keeping it moist and workable.
• Extends the growing season – Tender crops like tomatoes, zucchinis, eggplant, and capsicum survive longer.
• Improved germination – Seeds sprout faster because the soil temperature stays more stable.
• Less frost damage – Even cold-sensitive crops like basil and strawberries can continue growing.

How to Manage Heat in a Polytunnel on Hot Days (40°C+)

Since Western Australia experiences extreme summer temperatures, managing heat inside a polytunnel is crucial to prevent plant stress, wilting, and crop failure. Here are the best strategies to keep your tunnel cool and productive.

1. Maximise Ventilation

• Roll-up Sides & Open Doors – The simplest and most effective way to reduce heat is by allowing natural airflow. Haygrove Garden Tunnels have manual roll-up sides, which significantly lower internal temperatures.
• Position the tunnel to catch prevailing winds – A well-placed polytunnel benefits from natural cross-ventilation, preventing excessive heat buildup.

2. Use Shade to Reduce Heat Load

• Install a Shade Cloth – A 30–50% shade cloth over the tunnel helps reduce direct sun intensity while still allowing enough light for growth.
• Use Internal Shade Netting – Hanging shade netting inside can protect delicate crops like lettuce, spinach, and strawberries from scorching.
• Grow Tall Crops as Natural Shade – Position taller plants (e.g., tomatoes, beans, corn) on the sunniest side to act as a living shade barrier.

3. Increase Humidity & Cool Through Evaporation

• Dampen the Polytunnel Floor – Watering the ground early in the morning helps cool the air as it evaporates, reducing the temperature by several degrees.
• Use a Misting System – A fine misting system or fogging nozzles can drop temperatures by 5–10°C, especially during peak heat.
• Keep Water Trays Inside – Placing shallow trays or barrels of water inside increases humidity and reduces heat stress for plants.

4. Adjust Watering Practices to Reduce Heat Stress

• Water Early in the Morning or Late Afternoon – Helps prevent rapid evaporation and allows plants to absorb moisture before the heat of the day.
• Mulch Heavily – Apply straw, sugar cane mulch, or compost around plant bases to keep soil cool and retain moisture.
• Deep Watering, Less Frequently – Encourages roots to grow deeper, where soil remains cooler.

5. Choose Heat-Resistant Crops

Some plants thrive in heat with proper care. For WA polytunnels, the best summer crops include:

• Tomatoes, capsicum, eggplant, and chilies – Thrive with proper ventilation and watering.
• Cucumbers, pumpkins, and zucchinis – Heat-loving crops that benefit from extra shade.
• Melons (rockmelon, watermelon) – Naturally adapted to hot climates.
• Sweet corn and beans – Can provide shade for other crops.
• Basil, rosemary, and oregano – Mediterranean herbs that tolerate high temperatures.

6. Reflect Heat Away from the Tunnel

• Light-Colored Ground Cover – White mulch, reflective film, or straw reflects sunlight away from the soil, keeping the tunnel cooler.
• Exterior Shade Structures – A simple shade sail or tall trees planted nearby can help reduce sun exposure during peak hours.

7. Plan for Temperature Swings

• Extreme daytime heat can quickly turn into cool nights, which can also stress plants.
• Keeping ventilation consistent and ensuring the tunnel doesn’t overheat during the day will help crops adjust to natural temperature fluctuations.

✅ With good airflow, shading, and cooling methods? It can stay at 35–40°C, allowing heat-tolerant crops to thrive and produce high yields.