How to Keep Plants Warm During Winter?

In this part, we’ll give you 12 strategies to keep indoor and outdoor plants warm in winter.

Keep Indoor Plants Warm in Winter

Typically, indoor plants thrive in temperatures ranging from 60°F to 75°F (15°C to 24°C). As temperatures drop in winter, many houseplants may suffer from significant temperature fluctuations due to drafts, heating systems, and varying sunlight exposure. Facing the cold stress, many indoor plants may experience wilting, leaf drop, or even death. Therefore, it is crucial to take proactive measures to keep indoor plants warm in winter.

How to Keep Indoor Plants Warm in Winter

1. Position Near Windows

Place your plants close to south or west-facing windows where they can receive maximum sunlight. The warmth from the sun will help keep the plants cozy during the day. Just be cautious of drafts from windows and adjust their position if they get too cold at night.

2. Place near the Heat Sources

Take advantage of electrical appliances that can produce heat. For instance, you can place your indoor plants on the top of refrigerators and consecutively keep them warm. Alternatively, you can place them near a heating radiator. As radiators emit warmth, they can help maintain a cozy temperature for your plants. However, it’s essential to monitor the distance between the plants and the radiator to prevent overheating or drying out the soil too quickly.

3. Group Plants Together

By clustering your plants in one area, you create a microclimate that benefits all the plants involved. This arrangement allows them to share moisture through transpiration, which not only increases the humidity in the immediate environment but also helps prevent the dry air that often plagues indoor spaces in winter. 

Additionally, when plants are close together, they can generate and retain warmth more effectively than if they were spread out across a room. The collective heat produced by their respiration helps to elevate the overall temperature of the grouping. This is particularly important for sensitive species that thrive in warmer conditions, as it shields them from cold drafts and temperature fluctuations that can occur in more isolated spots. Furthermore, a clustered arrangement can enhance light distribution, allowing shorter plants to benefit from the shade provided by taller ones while also maximizing exposure to available light sources.

4. Adjust Watering Frequency

During the winter, many indoor plants enter a dormant phase as they respond to reduced light and cooler temperatures.  This means that they require significantly less water than they do during the active growing season.  This shift requires you to adjust the watering routine to ensure that you provide only what is essential for maintaining their health. Overwatering during this period can lead to waterlogged soil, which is a primary cause of root rot and can severely damage or even kill your plants.  By allowing the top layer of soil to dry out between waterings, you create a more favorable environment for root health while also helping to keep the soil warmer.

5. Add Insulation Materials

Simply wrapping insulation items around the pot can make a big difference. You can wrap the plant pots with bubble wrap to retain heat for indoor plants. This will create an insulating layer around the pot. Also, you can place smaller pots inside larger ones that are filled with insulating materials like newspaper. This can further protect root rot from cold.

6. Create a Humidity Dome

To keep seedlings or small plants warm overnight, use a transparent plastic cover or a humidity dome to create a nurturing environment during the cold months. This method effectively traps warmth and moisture, mimicking the conditions of a mini greenhouse, and controlling the grow room climate. 

The transparent material allows sunlight to penetrate while retaining heat.  Additionally, the humidity dome helps maintain higher humidity levels around the plants.  By reducing evaporation and creating a stable microclimate, this approach not only keeps the plants warm and hydrated but also fosters faster growth and healthier development.  Furthermore, it is important to regularly monitor the moisture levels inside the dome. This will prevent excess condensation, which can lead to mold or rot.

Keep Outdoor Plants Warm in Winter

If you have to keep your plants outside, it is important to maintain an ideal temperature range. Generally, most outdoor plants thrive best when temperatures are kept above 40°F (4°C). For tender plants, such as tropical varieties, it is advisable to keep them in environments where temperatures do not drop below 50°F (10°C). Conversely, hardy plants can tolerate lower temperatures but should ideally be protected when temperatures approach freezing, particularly when frost is expected, which occurs at 32°F (0°C). In this part, you’ll learn several proactive measures to keep outdoor plants warm during winter.

How to Keep Outdoor Plants Warm in Winter

1. Cover Plants with Frost Cloths

If you cannot move plants indoors, you can cover them with frost cloths or blankets to against freezing temperatures. These materials trap heat radiating from the ground while shielding plants from frost and harsh winds. It’s important to remove covers during the day to allow sunlight in and prevent overheating.

2. Watering Before Frost

Watering your plants before a cold snap can help them withstand freezing temperatures better. Moist soil retains heat more effectively than dry soil, which can help protect roots from freezing damage. However, be careful not to overwater, as soggy conditions can lead to root rot.

3. Adjust Watering Routine

During winter, many plants enter dormancy and require less water. Reducing watering frequency helps prevent root rot and keeps the soil warmer, ensuring that plants remain healthy through the colder months.

4. Add a Layer of Mulch

Applying a thick layer of mulch around your garden beds can significantly help insulate the soil and retain moisture. Organic materials like straw, wood chips, or dried leaves serve as effective insulators, protecting plant roots from freezing temperatures while also regulating soil temperature fluctuations.

5. Create Windbreaks

Protecting your plants from icy winds is essential for their health. Construct windbreaks using burlap or other porous materials to shield vulnerable plants from cold gusts that can strip leaves or branches. Positioning these barriers strategically around your garden can help maintain a warmer microclimate for your plants.

6. Invest in Mini Greenhouses

Mini greenhouses, Cattle Panel greenhouses, or cold frames create a controlled environment for plants, trapping warmth and protecting them from the elements. These structures allow for sunlight penetration while providing insulation.