How to Use Row Covers to Protect Winter Crops

Winter gardening can be a rewarding endeavor, offering fresh produce when most gardens are dormant.

However, cold temperatures, frost, and pests can pose significant challenges. One of the best ways to shield your winter crops from these threats is by using row covers. 

This post will explain what row covers are, why they are beneficial for winter crops, and how to properly use them for optimal results.

What Are Row Covers?

Row covers are lightweight fabrics or materials used to protect plants from cold weather, pests, and even harsh sunlight. 

They create a microenvironment that helps extend the growing season and safeguard crops. 

There are various types of row covers, each offering different levels of protection depending on your needs:

1. Lightweight Row Covers

These covers are primarily used for pest control. They offer minimal temperature protection but are great for keeping insects away from your crops.

2. Medium-weight Row Covers

This type offers moderate frost protection and helps maintain a stable growing environment during cooler weather. 

They are perfect for early fall and late spring planting but may not provide enough insulation for deep winter.

3. Heavyweight Row Covers

Designed for maximum frost protection, heavyweight row covers are thick enough to trap warmth and protect plants from freezing temperatures. 

These are the best choice for winter crops when temperatures dip significantly.

Why Use Row Covers for Winter Crops?

1. Frost Protection

Frost is one of the biggest threats to winter crops. A well-fitted row cover can trap heat from the soil and create a warm buffer, protecting plants from frost damage.

2. Extending the Growing Season

Row covers allow you to start planting earlier in the fall and continue growing crops well into the winter. This extends your harvest period, making your garden more productive.

3. Pest Control

Even in winter, some pests, such as aphids and cabbage worms, can wreak havoc on your crops. Row covers act as a barrier, preventing these pests from reaching your plants.

4. Wind Protection

Harsh winter winds can dry out plants and cause physical damage. Row covers shield crops from strong winds, reducing stress on plants.

5. Increased Yield and Plant Health

By creating a controlled environment, row covers help maintain optimal growing conditions. This can lead to healthier plants and higher yields.

Best Winter Crops to Grow Under Row Covers

Not all crops are suitable for winter growing, but many cold-hardy varieties thrive under the protection of row covers. Some of the best crops to grow include:

✅ Kale

One of the most cold-hardy vegetables, kale continues to produce well into winter under a row cover.

✅ Spinach

Spinach can survive temperatures down to 20°F, but row covers can help extend its growth and prevent frost damage.

✅ Carrots

Carrots can be overwintered in the garden with the help of row covers, giving you a fresh harvest during the colder months.

✅ Lettuce

Winter varieties of lettuce can tolerate some frost, but row covers help them thrive even when temperatures drop below freezing.

✅ Broccoli and Cauliflower

These cool-season crops benefit from the insulation provided by row covers, which protect them from frost and wind.

How to Install Row Covers for Winter Crops

Proper installation of row covers is essential for protecting your winter crops. Follow these steps to ensure your row covers are effective:

1. Choose the Right Type of Row Cover

Depending on the severity of your winter, select a row cover that offers the necessary level of protection. 

For mild winters, medium-weight covers might be sufficient, but if you experience heavy frosts, opt for heavyweight row covers.

2. Create a Support Structure

Row covers should not rest directly on your crops, especially if you're using heavier materials. 

Create a support structure, such as hoops or frames, to keep the fabric elevated above your plants. 

You can make hoops using PVC pipes, wire, or flexible rods that arch over the crop row.

3. Cover the Crops

Drape the row cover over the support structure, making sure it reaches the ground on both sides. This ensures that no cold air can seep underneath the cover.

4. Secure the Edges

To prevent the row cover from blowing away or allowing pests in, secure the edges by burying them in soil or weighing them down with rocks, bricks, or sandbags. 

Make sure the cover is taut but not too tight, as this can restrict airflow.

5. Monitor the Temperature

Row covers trap heat, but they can also cause overheating during sunny days. Monitor the temperature under the cover and vent it by lifting the edges on warmer days to allow for airflow.

6. Adjust as Necessary

As your crops grow, adjust the row covers to give them enough space. Also, as the season progresses, you may need to swap lighter covers for heavier ones to provide more insulation as temperatures drop.

Row Cover Maintenance Tips

1. Check for Tears

Regularly inspect your row covers for holes or tears. Even small gaps can let in cold air or pests. Patch any damage with fabric repair tape or needle and thread.

2. Remove Snow Accumulation

If you live in an area with heavy snowfall, the weight of the snow can collapse the row covers. Regularly brush off accumulated snow to prevent damage.

3. Watering Under Row Covers

Since row covers can trap moisture, you won’t need to water as frequently. However, you should check the soil moisture occasionally to ensure your crops aren’t drying out.

4. Remove When Not Needed

Once the worst of winter has passed or your crops are ready for harvest, remove the row covers.

Keeping them on too long can inhibit pollination for crops that flower in spring and cause overheating in warmer temperatures.

Additional Considerations

1. Mulching for Extra Insulation

While row covers provide significant protection, you can increase their effectiveness by mulching around the base of your crops. 

Organic mulch, such as straw or leaves, provides additional insulation, keeping the soil warmer for longer.

2. Double Covering for Extra Cold

In extremely cold climates, you can use two layers of row covers—one lightweight and one heavyweight—to provide even more insulation. 

Just be mindful of the reduced airflow, and vent the covers regularly to prevent moisture buildup.

3. Crop Rotation and Row Covers

If you’re practicing crop rotation, ensure that your row covers are compatible with the new planting scheme each year. 

The covers should be adaptable to different crop heights and types.

Common Mistakes to Avoid

1. Using the Wrong Weight of Row Cover

Lightweight row covers won’t provide adequate frost protection in severe winters, while heavyweight covers can cause overheating in milder climates. 

Always choose the appropriate weight for your conditions.

2. Not Venting on Warm Days

Row covers can trap heat, which is beneficial during cold nights but can be harmful on warm days. Not venting the cover can lead to overheating and stress on your plants.

3. Improper Sealing

If the edges of the row cover aren’t properly secured, cold air and pests can get in, reducing the effectiveness of the cover. Always make sure the cover is sealed tightly around the edges.

4. Neglecting Snow Removal

Allowing snow to pile up on top of row covers can damage both the cover and the plants underneath. Make sure to remove snow regularly.

Conclusion

Using row covers to protect your winter crops is a simple yet highly effective method to extend your growing season, shield plants from frost, and prevent pest damage. 

Whether you’re growing kale, spinach, or carrots, row covers will give your crops the extra boost they need to survive and thrive through the winter season.