Find out how to care and maintain your succulents during colder months, why forty degree is the limit for succulents, as well as what other temperatures could cause damage. During the cooler months, the plant can grow quite happily in temperatures that are as low as 40 degrees Fahrenheit, whereas, during the summer, the string of dolphin succulents can withstand temperatures as high as 80 degrees Fahrenheit. This may seem a bit labor-intensive, but E.