How to Overwinter Your Garden

Overwintering is key to protecting your tender plants during freezing weather. Every bulb, flower, vegetable, shrub, and tree in your garden has ideal growing conditions, with a primary factor being how much cold the plant can handle. When temperatures drop below freezing, your plants need overwintering.

Native plants that grow well in your USDA hardiness zone should be fine without extra protection. However, tender plants or those that don't grow in your zone need special care to survive the cold weather. Not taking essential steps to overwinter your plants can negatively affect their health.

Overwintering can be as simple as covering plants and moving potted plants indoors, but there are certain steps to protect in-ground plants during winter. If you have never overwintered your garden before, this guide will teach you how to successfully overwinter plants to help them survive, thrive, and come back season after season.

What is Overwintering

Overwintering is the practice of providing additional protection to plants for winter weather. It ensures the buds and fruits of the next season stay safe from icy winds. New plants, tropical plants, and plants that are not in their ideal hardiness zone will need extra protection during freezing weather to survive.

With a little precaution, overwintering can save you money and prevent stress, ensuring your plant can survive for years. You can also grow plants non-hardy in your region. Container plants also benefit from overwintering as it prevents their roots from freezing. There are several ways to protect your plants and vegetables from frost, so you don't lose all plants in winter.

Steps to Overwinter Your Garden

Here is how to overwinter your plants and protect them from cold weather.

Prune Your Plants

Perennials that can withstand low temperatures go dormant in winter. Their leaves fall off and come back the following spring. To help your plants survive this dormancy period, remove the extraneous branches to reduce the parts that plants need to be nourished.

Cut back dead wood from shrubs and trees and consider cutting up to one-third of evergreen or semi-evergreen perennials. After pruning, cover the plant's base with mulch to retain heat. Hardy plants such as rhododendrons, azaleas, and hibiscus can handle these months and grow again in spring.

Mulch Plants

Adding a thick layer of mulch to young shrubs, sapling trees, roses, perennials, and other shrubs with shallow roots is the simplest way to protect their roots against winter chill. Many types of mulch are available for the garden, from compost and wood chips to store-bought mulch.

Mulching around the base will provide insulation to roots and prevent them from dying in winter. Additionally, this is an excellent opportunity to fertilize your soil so it is fertile and nutrient-rich in spring.

Cover Plants to Protect them From Frost Damage

In addition to mulching, you need to shield the top of tender plants from frost damage. You can use a frost fabric or row cover to cover plants. Covering is a good way to overwinter vegetables, fruit trees, and plants that are not hardy in frost conditions. Plants that cannot be moved indoors can be covered and wrapped with burlap or cloth for insulation. A cold frame is another way to protect smaller plants and seedlings from frost. It is a wooden frame that goes over plants during winter.

Another excellent way to overwinter plants is to use a greenhouse for protection. You can make a small DIY greenhouse if you don't have space for a large house. However, avoid heating your greenhouse when overwintering plants because it can cause them to wilt in high temperatures.

Build Structures

Build a simple support structure around the mature plants that can't be moved. It can be made from wood stakes, rebar, PVC pipe, and other materials. This structure will allow the protective covering to settle over the plant. Stretch frost fabric, burlap, or an old blanket over these frames and secure them.

Cloches are also useful for small plants. Don't prune plants before protecting them in this way. Make sure the structure is large enough to accommodate the entire plant.

Move Plants to Warm and Protected Locations

If your plants can't survive frozen ground, you need to dig them up and move them to a moderately cold and dark location like a garage, basement, shed, or any other suitable location where temperatures can stay between 20-40°F. This overwintering method works well for tubers, corms, and bulb-forming plants. Simply cut the leaves, dig up the plant, remove all dirt, and store them in a warm place.

Move Potted Plants Indoors

The easiest way to overwinter potted plants is to move them indoors but inspect them first to ensure you are not bringing pests inside. Herbs and tender plants can be transplanted into pots and overwintered in a house, porch, greenhouse, or unheated garage. This also works for young plants that still need to establish deep roots. Choose a protected, frost-free location for the plants. Many garden plants require sunlight, so keep them on a sunny windowsill.

Which Plants Need Overwintering

Tender bedding, ornamental shrubs, unique roses, and less hardy plants will need overwintering. Potted plants also benefit from winter protection. Let's look at other plants that require extra care during winter.

Tender Perennials

They can suffer from harsh winter conditions, so place them in a sheltered, overwintering position. If the planted location is protected and the soil has good drainage, you can overwinter the plants growing in beds and borders where they are planted.

To protect the plant's roots, cover the base with a thick layer of mulch. During extended cold spells, cover plants with a cloche, cold frame, or other cover to add further protection. Once the cold snap is over, you can remove the protection.

Corms, Tubers, and Bulbs

Not all bulbs can survive freezing ground temperatures. Plants like dahlias, cannas, elephant ears, and gladiolus can be dug up, kept in pots, and stored in a frost-free place. Carefully pull the bulbs like corm, tuber, or rhizome, remove the soil, and allow them to dry first before storing.

Check them regularly throughout the winter to ensure they haven't rotten. Once the soil starts getting warm, put them back in the ground, where they will come out of dormancy.

Immature Shrubs

Immature shrubs and shrubs with shallow roots also need winter protection for a few years after planting. Mulching and wrapping prevent their immature root systems from drying and protect thin limbs from snow, ice, and high winds.

The Bottom Line

Overwintering your garden is an excellent way to protect fragile plants from the freezing temperatures of winter. This technique allows you to keep your plants in your garden for years that normally don't survive several years. It also allows you to cultivate plants of unique sizes and characteristics. What's more? Overwintering will enable you to grow unusual plants in your garden.

So, this winter, give your plants a better chance to grow by protecting them. First, you need to know if your garden plants are hardy in your zone. Find your zone and check the plant's hardiness on the USDA website for this. A hardy plant means it can handle lower temperatures. If it is not hardy in your zone, you need to overwinter it.