Not only do we need to prepare ourselves for the cold, snow and ice that we may see in the winter, but our gardens will benefit by getting a little TLC when the weather gets frightful. Portland Nursery and the Portland Fruit Tree Project offer the following suggestions.
Potted plants have less insulation from the cold and can be moved to a cool room of the house, or the garage, for the duration of the most extreme temperatures. Even moving the containers close to the house, protected from cold winds if possible, can help them. Frost blankets are another option for containers that can’t be moved.
For borderline hardy plants like Hebe, Camellias and Star Jasmine, add mulch and cover the plants with a frost blanket. Plastic tarps are not recommended as they don’t allow for air circulation. Frost blankets should only be used temporarily as extended use can trap moisture, encouraging rot.
Consider wrapping trees that are not cold hardy below 20 degrees or young trees that have not had time to establish their root system. Any fruit that is left on the tree (i.e. Yuzu, loquat) should be harvested.
Shallow roots can be damaged by freezing air temperatures. Adding a layer of composted garden mulch or bark will help protect them. Newly planted trees will be more resilient with a good layer of mulch under their canopy.
Kale, chard, onions, garlic and shallots are fine left uncovered, however broccoli and cabbages should be protected with row covers, frost blankets or cold frames. If temperatures dip to 17 degrees for a prolonged period, lettuce should be harvested.
Cold temperatures accompanied by precipitation will often provide adequate moisture. To be on the safe side, check for watering needs. Water helps roots remain durable while also protecting against desiccation.
More seasonal tips by month at portlandnursery.com.