Geraniums, also known as Pelargoniums, are popular flowering plants that come in a wide range of varieties and cultivars. When it comes to cold tolerance, geraniums generally fall into two categories: hardy geraniums and tender geraniums.
Hardy geraniums, also called cranesbills, are known for their ability to withstand colder temperatures. These plants are typically native to temperate regions and have adapted to survive freezing temperatures. Depending on the specific species and cultivar, hardy geraniums can tolerate cold temperatures ranging from 20 degrees Fahrenheit or lower.
I have personally grown several hardy geraniums in my garden, and they have proven to be quite resilient in colder climates. Even in regions where winter temperatures can drop well below freezing, these plants have survived and thrived. Some of the hardy geranium varieties that are known for their cold tolerance include Geranium sanguineum, Geranium macrorrhizum, and Geranium nodosum.
On the other hand, tender geraniums, which are the more commonly known geraniums with showy flowers, are not as cold hardy as their hardy counterparts. These tender geraniums are often grown as annuals or brought indoors during the winter in colder regions. They are native to regions with milder climates, such as the Mediterranean.
Tender geraniums can typically tolerate temperatures down to around 32 degrees Fahrenheit, but prolonged exposure to colder temperatures can damage or kill them. I have had experiences where my tender geraniums suffered frost damage when I left them outside during a surprise late spring frost. However, with proper protection or by bringing them indoors during cold spells, you can extend their lifespan.
It is worth noting that while geraniums can tolerate cold temperatures, they still require some care to ensure their survival. Providing them with well-drained soil, adequate water, and proper mulching can help protect their roots during freezing conditions.
In addition to cold tolerance, geraniums also have varying levels of heat tolerance. Some varieties can withstand high temperatures and full sun exposure, while others may struggle in intense heat. For example, the hardy geraniums I mentioned earlier can tolerate full sun in hotter regions, where temperatures can soar to 100 to 110 degrees Fahrenheit.
To summarize, the cold tolerance of geraniums depends on the specific variety. Hardy geraniums are generally more cold tolerant and can withstand temperatures as low as 20 degrees Fahrenheit or lower. Tender geraniums, on the other hand, are less cold hardy and can typically tolerate temperatures down to around 32 degrees Fahrenheit. Providing proper care and protection can help ensure their survival in colder climates.
