Lobelia plants, specifically the Lobelia erinus species, are annuals and are not able to survive in cold weather conditions. These plants are not hardy to freezing temperatures and will not survive if exposed to frost or extreme cold.
However, there are other varieties of Lobelia, such as the Lobelia x speciosa, that are perennials and can withstand colder temperatures. These perennial varieties are hardy to a range of 5 to 14 degrees Fahrenheit (-15 to -10 degrees Celsius), depending on the specific species and cultivar.
In my personal experience, I have grown Lobelia plants in my garden, both annual and perennial varieties. The annual Lobelia erinus was a beautiful addition to my summer garden, with its vibrant blue, pink, or white flowers. However, as soon as the temperatures dropped in the fall, the plants started to wither and eventually died off with the first frost.
On the other hand, the perennial Lobelia x speciosa varieties, such as ‘Fan Scarlet’ or ‘Queen Victoria’, have proven to be much more resilient to colder temperatures. I have witnessed these plants survive through winter in my garden, even with temperatures dropping below freezing. They may die back to the ground in colder regions but will regrow from their roots in the following spring.
To protect Lobelia plants from cold weather, it is important to provide them with proper care and attention. Here are some tips to help ensure their survival:
1. Plant selection: If you live in an area with cold winters, opt for perennial Lobelia varieties, such as Lobelia x speciosa, which are more cold-hardy than annual species.
2. Planting location: Choose a sheltered location in your garden that offers some protection from harsh winds and excessive cold. This can help create a microclimate that is more favorable for Lobelia plants.
3. Mulching: Apply a layer of organic mulch around the base of the plants in late fall or early winter. This will help insulate the soil and protect the roots from freezing temperatures.
4. Watering: Proper watering is crucial for the survival of Lobelia plants in cold weather. Ensure that the plants are adequately watered throughout the growing season, but reduce watering in the fall as the plants prepare for dormancy.
5. Cutting back: In regions with extremely cold winters, it is advisable to cut back the foliage of perennial Lobelia plants in late fall or early winter. This will help divert energy to the roots and protect the plant during dormancy.
6. Division: Every few years, consider dividing mature perennial Lobelia plants in early spring. This not only helps rejuvenate the plants but also allows you to propagate them and increase their numbers in your garden.
While Lobelia erinus, the annual variety, cannot survive cold weather and freezing temperatures, there are perennial Lobelia x speciosa varieties that are hardy and can withstand colder conditions. By selecting the appropriate species, providing proper care, and implementing protective measures, it is possible to enjoy the beauty of Lobelia plants in your garden even in colder climates.