How Do Greenhouses Work In Winter?

How do Greenhouses Work In Winter?

Imagine, for a moment, a lush oasis nestled in the midst of a winter wonderland. Surrounded by snow-covered landscapes, this haven is a testament to the remarkable ingenuity of greenhouses. But how exactly do these marvels of horticulture endure the cold, icy grip of winter? In this article, we will uncover the fascinating inner workings of greenhouses during this frosty season, revealing the secrets behind their ability to sustain vibrant plant life even when faced with the harsh challenges of winter. So, bundle up and prepare to discover the wondrous world of winter greenhouses!

How do Greenhouses Work In Winter?

Creating a Suitable Environment

During winter, it is essential to create a suitable environment inside the greenhouse to ensure the optimal growth of your plants. Three key factors to consider are maintaining temperature, controlling humidity levels, and regulating air circulation.

Maintaining Temperature

Greenhouses need to be properly insulated to maintain the ideal temperature during the colder months. One effective method is the use of double-glazed or triple-glazed glass panels. These panels provide better insulation by trapping air between the layers, reducing heat loss. Another option is polyethylene or polyvinyl chloride (PVC) covers, which are more cost-effective but still provide insulation.

To further regulate temperature, consider using thermal shades and blankets. These can be installed on the greenhouse walls and roof, providing an extra layer of insulation. Thermal shades also allow for easy adjustment of light levels, which is important for the overall health of the plants.

Controlling Humidity Levels

Humidity control is crucial in winter to prevent excess moisture buildup, which can lead to diseases and mold growth. Proper ventilation plays a significant role in regulating humidity levels. Consider installing roll-up or hinged side walls, allowing you to control the amount of airflow. Roof ventilation is another option, as it allows warm air to escape while bringing in fresh air. mechanical ventilation fans can also be used to ensure adequate air exchange.

Regulating Air Circulation

Air circulation is essential in maintaining a healthy greenhouse environment. It helps distribute heat evenly and prevents the buildup of stagnant air, which can lead to disease. Ensure that the greenhouse has proper vents and fans to promote air circulation. By strategically placing these vents and fans, you can create a gentle breeze that circulates throughout the greenhouse.

Insulation Methods

Insulation is key to retaining heat inside the greenhouse during winter. Here are some effective insulation methods to consider:

Double-Glazed or Triple-Glazed Glass Panels

Double-glazed or triple-glazed glass panels provide excellent insulation by trapping air between the layers. This trapped air acts as a barrier, reducing heat loss and maintaining a stable temperature inside the greenhouse.

Polyethylene or Polyvinyl Chloride (PVC) Covers

Polyethylene or PVC covers are affordable options that still provide insulation. These materials are lightweight and can be easily installed on the greenhouse structure. They effectively trap heat and protect the plants from harsh weather conditions.

Thermal Shades and Blankets

Thermal shades and blankets are additional insulation options that can be installed inside the greenhouse. These shades can be adjusted to control light levels and temperature. They provide an extra layer of insulation, helping to retain heat and regulate the overall environment.

Heating Systems

In colder climates, a reliable heating system is vital to keep the greenhouse warm during winter. Here are some common heating systems to consider:

Electric Heaters

Electric heaters are a popular choice for small to medium-sized greenhouses. They are easy to install and provide consistent heat. Electric heaters can be controlled with thermostats, allowing you to maintain the desired temperature for your plants.

Gas and Oil Heaters

Gas and oil heaters are suitable for larger greenhouses. These heaters are more powerful and can generate a significant amount of heat. It is important to ensure proper ventilation when using gas or oil heaters to maintain air quality inside the greenhouse.

Wood-Burning Stoves

For those who prefer a more sustainable heating option, wood-burning stoves can be used to heat the greenhouse. They provide a rustic charm while generating ample heat. However, it is important to carefully manage ventilation and ensure proper safety measures.

Geothermal Heating

Geothermal heating utilizes the constant temperature of the Earth to regulate the greenhouse’s temperature. This system circulates water through pipes buried underground, absorbing heat from the ground in winter and releasing it into the greenhouse.

Heat Exchangers

Heat exchangers are a cost-effective option that utilizes surplus heat from nearby buildings or equipment. This method transfers excess heat to the greenhouse, reducing the need for additional heating sources.

Alternative Heat Sources

In addition to conventional heating systems, there are alternative heat sources that can be utilized:

Solar Heating

Solar heating harnesses the sun’s energy to warm the greenhouse. This can be achieved through passive solar techniques or by installing solar panels to generate electricity for heating systems. Solar heating is a sustainable and eco-friendly option.


Composting can generate heat, which can be harnessed to warm the greenhouse. By composting organic matter such as plant waste, you can create a natural heat source. The heat generated during decomposition can be distributed within the greenhouse through pipes or vents.

Biomass Burners

Biomass burners burn organic materials such as wood chips, pellets, or agricultural waste to generate heat. These burners are an environmentally friendly option and can be used as a primary or backup heat source for the greenhouse.

biomass burner in greenhouse

Cold-Weather Plant Selection

Choosing cold-hardy plants is essential for successful greenhouse gardening during winter. Here are some factors to consider when selecting plants:

Choosing Cold-Hardy Plants

Selecting plant varieties that are naturally resistant to freezing temperatures is crucial. Look for cold-hardy plants that can withstand the lowest temperatures experienced in your region. Examples of cold-hardy plants include kale, spinach, lettuce, and certain varieties of herbs.

Utilizing Plant Covers or Cloches

To protect more delicate plants, consider using plant covers or cloches. These coverings create a microclimate around the plants, providing an additional layer of protection against frost and cold temperatures. Cloches can be made from glass or plastic and are placed over individual plants or small groupings.

Crop Rotation

Implementing crop rotation in your greenhouse can help optimize plant health and reduce the risk of disease and pest infestations. By rotating crops, you can also take advantage of the different temperature requirements of various plants, ensuring overall success throughout the winter season.

Ventilation Systems

Proper ventilation is crucial for maintaining good air quality and regulating temperature and humidity levels. Here are some ventilation systems commonly used in greenhouses:

Roll-Up or Hinged Side Walls

Roll-up or hinged side walls allow for easy adjustment of airflow and temperature inside the greenhouse. These walls can be opened during the day to allow fresh air in and closed at night to retain heat.

Roof Ventilation

Roof ventilation systems allow warm, stagnant air to escape while enabling fresh air to enter the greenhouse. This helps maintain optimal temperature and humidity levels while preventing the buildup of excess moisture.

Mechanical Ventilation Fans

Using mechanical ventilation fans can promote air circulation and control humidity levels. By strategically placing fans, you can ensure that air circulates evenly throughout the greenhouse, preventing the development of stagnant air pockets.

How do greenhouses work in the winter time?

Insulated Flooring

Proper insulation also extends to the greenhouse flooring. Here are some insulation methods for greenhouse flooring:

Packing Material

Using packing materials such as gravel or crushed stone as a base layer helps improve drainage and insulation. These materials prevent direct contact between the ground and the greenhouse flooring, reducing heat loss.

Insulating Boards

Insulating boards, made from materials such as foam or polyurethane, can be installed beneath the flooring to provide additional insulation and prevent heat loss.

Radiant Heating

Radiant heating systems can be installed under the greenhouse flooring to provide consistent and efficient heat. These systems use a network of tubes through which warm water or heated air circulates, ensuring the entire greenhouse floor is evenly heated.

Energy Efficiency Measures

Implementing energy-efficient measures in your greenhouse not only helps reduce energy consumption but also promotes sustainability. Consider the following measures:


Proper weatherstripping ensures that doors and windows are tightly sealed, preventing drafts and heat loss. This simple and cost-effective measure helps retain heat and reduce energy waste.

Thermal Screens

Installing thermal screens can help reduce heat loss during the night. These screens act as an additional layer of insulation, optimizing heat retention and preventing cold drafts.

Insulated Doors

Replacing or adding insulation to greenhouse doors helps maintain a stable temperature and prevents heat loss. Insulated doors are designed to minimize heat transfer, ensuring an efficient and well-insulated greenhouse.

Energy-Efficient Lighting

Switching to energy-efficient lighting, such as LED or fluorescent bulbs, can significantly reduce energy consumption. These lighting options provide adequate light for plant growth while minimizing energy waste.

using a grow light in a greenhouse

Snow and Ice Management

Winter weather conditions can pose challenges for greenhouse maintenance. Here are some snow and ice management measures to consider:

Thermal Blankets

Covering delicate plants with thermal blankets can provide protection against frost and freezing temperatures. These blankets act as an additional layer of insulation, helping to retain heat and preventing damage to the plants.

Heating Cables

Installing heating cables beneath the greenhouse benches or flooring can help prevent snow and ice buildup. These cables generate heat, melting the snow and ice and preventing them from accumulating and causing damage.

Clearing Snow and Ice

Regularly clearing snow and ice from the greenhouse roof and walkways is essential to prevent excess weight and potential structural damage. Use appropriate tools and techniques to safely remove snow and ice without damaging the greenhouse or plants.

Monitoring and Automation

Monitoring and automating systems in the greenhouse can greatly simplify maintenance while ensuring optimal conditions for plant growth. Consider the following:

Thermostats and Sensors

Installing thermostats and sensors allows you to monitor temperature, humidity levels, and other environmental factors. These devices provide real-time data and can be programmed to automatically adjust heating, ventilation, and other systems based on preset parameters.

Automated Ventilation and Heating Systems

Automation systems can control and adjust ventilation and heating systems based on preset conditions. These systems can regulate temperature, humidity, and air circulation, freeing you from constant monitoring and providing a more efficient and stable greenhouse environment.

In conclusion, creating a suitable environment in your greenhouse during winter is crucial for the success of your plants. By maintaining temperature, controlling humidity levels, and regulating air circulation, you can provide the optimal conditions for plant growth. Insulation methods, such as double-glazed glass panels and thermal shades, help retain heat inside the greenhouse. Choosing the right heating system, utilizing alternative heat sources, and selecting cold-hardy plants are essential. Ventilation systems, insulated flooring, energy efficiency measures, snow and ice management, and monitoring and automation systems complete the comprehensive approach to greenhouse gardening in winter. With careful planning and implementation, you can enjoy a thriving greenhouse even during the coldest months.

how do greenhouses work in winter?