Winter can be a challenging time for plants, with freezing temperatures posing a threat to their survival. While the cold itself can be damaging, it’s often the dry conditions that accompany winter weather that cause the most harm.
Understanding when and how to water plants before a freeze helps maintain a healthy garden year-round. In this guide, we’ll go over best practices for watering plants before freezing temperatures hit, as well as other strategies to protect your plants from winter.
How Does Cold Weather Impact Plants?
Cold weather affects plants in several ways, and it’s not just the freezing temperatures that pose a threat. Winter winds and dry air can dehydrate plants, causing more damage than the cold itself. This is particularly true for evergreens, which continue to lose water through their foliage even in winter.
The Role of Water in Plant Protection
Water protects plants from cold damage. It acts as an insulator, helping to regulate temperature within plant cells. Plants with cells full of water are better equipped to withstand freezing temperatures. Additionally, moist soil tends to stay warmer than dry soil, providing an extra layer of protection for plant roots.
The Challenges of Winter Watering
Watering plants in winter can be more difficult than in other seasons. When the ground freezes, water turns into ice crystals, making it impossible for plant roots to absorb. Even dormant plants require some water throughout the year, so timing is essential to winter watering.
When To Water Plants Before a Freeze
When you water your plants makes a significant difference in how well they withstand cold temperatures.
Watering Before the Ground Freezes
For regions where the soil stays frozen all winter, fall is the prime time for watering. Water all plants well before the ground freezes solid. This gives plants the best chance of surviving long periods of frozen soil.
Watering During Occasional Freezes
In areas that experience only occasional freezing weather, water deeply a day or two before you expect a freeze. This is especially important if there has been insufficient rain or snowfall. When watering, saturate the entire root system. A good rule of thumb is to water an area the size of the plant’s drip line.
Special Attention for New Plantings
Newly planted trees and shrubs require extra care during freezing weather. Their root systems are less established, making them more vulnerable to cold damage. Additionally, disturbed soil around new plantings can allow cold air to penetrate deeper, harming the roots. Give these plants adequate water during fall to protect them in winter.
Best Practices for Watering Plants in Freezing Weather
To ensure the best protection for plants during freezing weather, follow these watering guidelines:
Timing and Temperature Considerations
Water when the air temperature is above 40°F to allow plants time to absorb moisture before temperatures drop. Avoid watering when there’s snow or ice on the ground, as this can lead to further freezing and damage. The best practice is to water early in the day, giving plants ample time to absorb moisture before nighttime temperature drops.
Watering Techniques
When watering in winter, focus on the root zone rather than wetting the foliage. Wet foliage can lead to ice formation and damage to leaves and branches.
It’s best to water deeply but infrequently. Once or twice per month should be enough for most plants during the dormant season. Be careful not to overwater, as cool soil can easily become waterlogged, leading to root rot and other issues.
Avoiding Common Mistakes
Certain watering practices can do more harm than good. Don’t use sprinkler irrigation to protect plants from frost unless you’re a commercial grower with specific knowledge and equipment. Also, don’t assume all plants need the same amount of water. Different species have varying water requirements, even in winter.
Additional Protection Strategies for Plants in Freezing Weather
While proper watering is important, there are other steps you can take to protect your plants from freezing temperatures.
Mulching for Insulation
Applying a layer of mulch around plants helps insulate the soil and protect roots from freezing. Use natural materials such as straw, leaves, or bark chips. Put a 2–3 inch layer around the base of the plants. Don’t pile mulch against the stems or trunks.
Covering Plants
For particularly vulnerable or valuable plants, consider using protective coverings. Options include:
- Frost cloths or blankets
- Burlap wraps
- Cardboard boxes or plastic containers (for smaller plants)
When covering plants, check that the covering extends to the ground to trap heat from the soil. Remove coverings during the day to allow sunlight and air circulation.
Creating Windbreaks
Winter winds can exacerbate cold damage by increasing moisture loss from plants. Create windbreaks using:
- Temporary fencing
- Burlap screens
- Strategic placement of hardier plants to shelter more delicate ones
Caring for Different Types of Plants in Freezing Weather
Different plants have varying levels of cold tolerance and require specific care during freezing weather.
Evergreens
Evergreens are susceptible to winter desiccation. To protect them:
- Water thoroughly before the ground freezes.
- Apply anti-desiccant sprays to reduce moisture loss from foliage.
- Provide windbreaks for exposed plants.
Perennials
Many perennials die back to the ground in winter but still require some care:
- Cut back dead foliage after the first frost.
- Apply a layer of mulch over the root zone.
- Avoid heavy watering, which can lead to crown rot.
Container Plants
Potted plants are more vulnerable to freezing because their roots are less insulated. To protect them:
- Move containers to a sheltered location, such as against a building or under an overhang.
- Group pots together to create a microclimate.
- Wrap pots in insulating materials such as bubble wrap or burlap.
Monitoring and Maintaining Plants During Winter
While regular monitoring and maintenance are important year-round, winter maintenance keeps your plants healthy and helps them survive the dormant season.
Checking for Signs of Stress
Inspect plants regularly for signs of cold damage or stress. Look for discolored or drooping leaves, cracked bark or stems, and plant heaving from the soil due to freeze-thaw cycles. These indicators can help you identify issues early and take appropriate action.
Adjusting Care as Needed
Prepare to adjust your care routine based on weather conditions and plant health. This may include providing additional protection during severe cold snaps, such as covering plants or moving potted plants indoors.
Adjust the watering frequency based on precipitation and temperature fluctuations so plants receive enough moisture without overwatering. If you notice damaged branches, prune them quickly to prevent further injury and potential disease entry points.
Preparing Plants for Spring
Spring may seem far away, but preparing plants during winter helps them thrive when warmer weather arrives. Keeping plants healthy and adequately protected during winter will lessen the risk of disease and stress when they regrow in spring.
As temperatures begin to rise, start gradually reducing extra winter protection to allow plants to acclimate to changing conditions. It’s also important to resume regular watering schedules before major growth spurts occur, ensuring your plants have the necessary resources to support new growth.
Final Thoughts About Watering Plants Before a Freeze
Protecting plants from freezing weather is essential for your garden or landscape. Each plant and garden is unique, so finding the best winter care routine may take some trial and error. With proper watering and protection, your plants can come back healthy and vibrant when spring arrives, ready to bring beauty and life back to their outdoor spaces.
Further Information
For more information on watering your plants and lawn, check out these articles and videos:
- Calculating Lawn Irrigation Costs (article)