Don’t kill your poinsettia with the cold, experts warn

Did you know that Mexico is the native home of the ever-popular poinsettia, and this means that this bright and colorful houseplant – with 80 per cent of poinsettias sold the traditional red, according to British Garden Centres – should never be left outside in the cold for too long?

Part of the Euphorbia family (Euphorbia pulcherrima), botanist and physician Joel Robert Poinsett introduced the plant to the United States in the 1820s.

'Poinsettias are very susceptible to extremes of temperature,' says Mike Futia, founder of Nerd Lawn. 'If a poinsettia is accidentally exposed to freezing temperatures, bringing them indoors and providing proper care is essential for the plant's recovery and further growth.'

Why poinsettias will suffer in the cold

Experts generally agree that this Christmas plant will grow outdoors in USDA zones 10 and 11, when temperatures are between 40-50˚F (4.4-10˚C). 

'Poinsettias can be left outdoors without worries in mild winter climates, such as the south. Areas such as Florida, Georgia, Louisiana, and Texas are ideal for keeping poinsettias outdoors in winter,' says Mike. 

'In these warm climates, they can be planted in the ground or in containers and will thrive with little care,' says Lindsey Hyland, founder of Urban Organic Yield. 'They can also be grown as annuals in colder climates if they are brought indoors when the weather turns cold.'

However, some regions in the US are simply too cold to leave poinsettias outside. 'Poinsettias cannot survive outdoors during winter in colder areas such as the northern Midwest, far Northwest, and much of the Northeast,' adds Mike. 

Emergency rescue

If you've accidentally exposed your poinsettia to too-cold conditions, you can rescue it by moving it back indoors as soon as possible. 'Try to keep the plant in a sunny spot and water it regularly,' says Lindsey. 'The leaves may look wilted at first, but they should recover over time.'

However, the one thing poinsettias really hate is extremes of temperature. Avoid making a common poinsettia temperature mistake and don’t shock your plant by bringing it straight in from the cold to a really warm and cozy house. Instead, it can be best to let it come back to room temperature slowly.