Winter is Coming: How to Protect Your Berlin Garden from Frost and Snow
The continental climate of Berlin brings cold, frosty winters. While a blanket of snow can look magical, frost and freezing temperatures can be deadly for many garden plants. With a few simple preparations in autumn, you can help your plants survive the winter and ensure they return stronger in spring.
Understanding the Danger: Frost vs. Freeze
A light frost occurs when temperatures dip to around 0°C, forming ice crystals on surfaces. This mainly damages tender leaves. A hard freeze (temperatures well below 0°C for several hours) freezes the water inside the plant's cells, which can cause them to burst and kill the plant.
1. The Mulch Blanket: Protecting the Roots
The most important part of a plant to protect is its root system. A thick layer of mulch acts like a warm duvet for the soil.
- What to use: Fallen leaves are perfect and free! You can also use bark mulch, straw, or compost.
- How to apply: After the first light frost but before the ground freezes solid (usually late October/November in Berlin), apply a 10-15 cm thick layer of mulch around the base of your sensitive perennials (like roses, lavender) and shrubs.
- Benefit: The mulch insulates the soil, protecting the roots from the freeze-thaw cycles that can heave plants out of the ground.
2. Covering Sensitive Plants
Some plants, especially evergreens like boxwood or newly planted shrubs, can suffer from frost damage or "winter burn" (dehydration from cold winds).
- Fleece Covers: Garden fleece (Vlies) is the best material. It's breathable and light. Wrap it loosely around the plant. Avoid plastic film, as moisture can get trapped underneath and freeze, causing more damage.
- When to cover: Cover plants when several days of hard frost are forecast. It's important to remove the covers on mild, sunny days to allow the plant to breathe and prevent overheating.
- For Roses: Mound soil or compost up around the base of your rose bushes (about 20 cm high) to protect the sensitive grafting union.
3. Potted Plants: Moving to Winter Quarters
Plants in pots are much more vulnerable to cold, as their roots are exposed on all sides. Most non-hardy balcony and terrace plants must be moved indoors.
- Tender Plants (Geraniums, Fuchsias, Mediterranean herbs): Bring them indoors before the first frost into a cool, bright place like a staircase, a frost-free garage, or a basement with a window. Water them sparingly throughout the winter.
- Hardy Potted Plants (some grasses, small conifers): Even hardy plants need root protection. Wrap the pot in bubble wrap or burlap and place it on a piece of styrofoam to insulate it from the cold ground. Move it to a sheltered spot against the house wall, out of the harsh east wind.
4. Snow: Friend or Foe?
A steady blanket of snow is actually a fantastic insulator! It protects the ground and the plants underneath from harsh winds and deep frost. Problems arise with:
- Heavy, Wet Snow: This can weigh down the branches of evergreen shrubs and conifers, causing them to break. Gently shake the snow off after a heavy snowfall.
- Clearing Snow: Avoid piling salty snow from your driveway or sidewalk onto your garden beds. The salt is toxic to most plants.
By taking these simple steps, you can tuck your garden in for the winter and look forward to a healthy, vibrant start in the spring. Always keep an eye on the long-term weather forecast to know when the first hard frosts are approaching.