Brrrrrrrrrrrr. Has anyone out there in the Bay Area been feeling a bit chilly? The temperatures are starting to rise, but last week was cold! While my friends on the East Coast may laugh at the West Coast’s weakness to cold weather, temperatures in the Bay Area have been chillier than they have in years. San Jose broke a record low set 82 years ago when it recently dipped to 30 degrees, while cities such as Oakland, Mountain View, and Napa also reached lower temperatures than they have in almost a decade.
But while we blast our heaters, bundle up, and drink hot chocolate what are our plants doing?
At many of our restoration sites, our plants are going through a dormant phase to resist injury from freezing night time temperatures. When plants are exposed to low temperatures their cells can freeze, limiting water and nutrient exchange. This causes the plant’s leaves and shoots to become limp and blackened. Soils may also freeze, limiting the uptake of water through the roots. When the morning sun begins to defrost plants, the sudden change in temperature causes more damage as the cell walls rupture.
But rest assured volunteers — your efforts planting our native California plants are not lost because our native plants are very hardy and adapted to surviving cold conditions. Some native perennial plants will go dormant in colder temperatures to reduce metabolic activity and therefore save energy.
There are two types of dormancy — predictive and consequential. Predictive dormancy is when the plant prepares for the cold as temperatures drop or water is limited. The plant will shed its leaves and halt active growth to store energy until conditions are more optimal. Consequential dormancy is when the plant reacts to cold temperatures after they have been reached. This is more common with unpredictable weather patterns that can vary at a rapid rate.
Our vegetable gardens at home are at greater risk than the shoreline plants. The first frosts have damaged my hopes of overwintering my bell peppers and eggplants in south Berkeley. Normally California is lucky to have great growing conditions throughout the year, allowing even some summer crops to survive the winter and blossom again the following year. However, unexpected temperatures this year may mean I’ll have to stick to my usual winter leafy greens.
If one is prepared, there are several measures you can take to prevent the cold weather from damaging your plants:
Unfortunately us humans can’t afford to go dormant for the winter (though it sounds great to lay in bed nice and warm all day) and the restoration department at Save The Bay isn’t slowing down. Big thanks to all our volunteers for braving the cold and helping to restore the Bay’s shoreline. We’ve successfully installed over 11,000 plants at our sites so far, and have a lot more to go. So bundle up and come plant with us this planting season!
Our full schedule of restoration programs can be found at savesfbay.org/volunteer.
I spent most of my life in Washington State before moving to the Bay area 7 years ago and I am used to the stormy winter weather of the Pacific Northwest. The people who know me best are aware that I love winter in the Bay area because I miss the rain and gray skies that have been so much a part of my life, and that I look forward to the first really big storm of the year with great anticipation and excitement.
This is also a time of year for great anticipation and excitement at Save The Bay. The Habitat Restoration Team has spent much of the spring, summer, and fall seasons collecting local native plant seeds, propagating plants, and carefully nurturing seedlings in our two native plant nurseries under the guidance of our Nursery Manager Doug Serrill. With the help of thousands of volunteers we currently have over 30,000 plants ready to go in the ground as soon as the first raindrops start falling in earnest. We have carefully watered our plantings throughout the year in our nursery and by installing the plants in tandem with the rains we give them the best opportunity to establish and grow and minimize the stress due to transplanting. With an adequate water supply during transplanting and during the first winter, the plants develop roots that are better able to survive the warm summers that are characteristic of our Bay area Mediterranean climate.
Our restoration staff and dedicated volunteers have diligently prepared our planting sites by removing non-native and invasive plant species, and our Senior Scientist, Laura Wainer has developed a planting strategy for each of our restoration sites to maximize native plant cover and diversity and to create valuable transition zone habitat at the edge of salt marshes around San Francisco Bay.
In other words – we are ready to go! Planting season at Save The Bay officially begins when the first significant storms of the year start rolling into the Bay area. This is my first planting season as the Habitat Restoration Director at Save The Bay, and I can’t wait to share in the excitement of installing the first plants of the season into the ground. Don’t be left out of the fun and excitement. With rains predicted for the coming weekend our planting season is upon us. We have 30,000 plants to install over the next 3-4 months. Come join us for a planting event and together we can celebrate the start of the rainy season!