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Poinsettia care

Poinsettia care: keep it alive, then make it bloom again

Keep it warm on the way home, since poinsettias are damaged below 10°C (50°F), then give it at least 6 hours of bright, indirect light, a room at 18 to 21°C (65 to 70°F), water when the surface feels dry, and no fertiliser while it is in bloom. It is not the deadly plant of legend: the ASPCA lists it as toxic to cats and dogs but generally over-rated in toxicity, and Pet Poison Helpline calls it only mildly toxic.

Taking it home

What is the temperature outside?

Sleeve or bag it5°C / 41°F

Below 10°C (50°F) poinsettias are damaged, and even a few minutes of cold can harm the bracts and leaves. Have it sleeved or put in a loose bag, and go straight to a warm car.

Sources: UMN Extension, poinsettia; Clemson HGIC 1561; Illinois Extension, caring for poinsettias; Penn State, poinsettias; Iowa State, poinsettias

Rebloom calendar

Dates for keeping this year’s plant and colouring it again.

Rebloom calendar

Colour again for Christmas 2027

Keep this year’s plant in bloom first: bright, indirect light for at least 6 hours a day, 18 to 21°C (65 to 70°F), water when the surface feels dry, and no fertiliser while it is in bloom (Clemson, University of Minnesota Extension).

  1. : Cut it back when the bracts fade

    Prune the stems to about 20 cm (8 in) tall. Start feeding when new growth appears: half-strength houseplant fertiliser every 3 to 4 weeks. (Clemson HGIC 1561; UMN Extension, poinsettia)

  2. : Repot

    Move it into a pot 5 to 10 cm (2 to 4 in) wider. Once nights stay above 10°C (50°F) it can go outdoors for the summer. (Clemson HGIC 1561)

  3. : Last day to pinch

    Through the summer, pinch out shoot tips to keep it bushy (Illinois: every 3 to 4 weeks), but not after 1 September, or flowers may not form in time. Bring it in before nights fall to 13 to 16°C (55 to 60°F). (Clemson HGIC 1561; Penn State, poinsettias; Illinois Extension, caring for poinsettias)

  4. : Start long nights

    Every night, 14 hours of complete darkness from 5 p.m. to 7 a.m. (17:00 to 07:00): a closet, or a box over the plant. By day give it 6 to 8 hours of bright sun. Keep it at 16 to 21°C (60 to 70°F); nights above 21 to 24°C (70 to 75°F) can delay or stop flowering, and even a small light leak can prevent it. (Penn State, poinsettias; Clemson HGIC 1561; Illinois Extension, caring for poinsettias; Maryland Extension, poinsettias)

  5. : Eight weeks of long nights

    Clemson gives 8 to 10 weeks of long nights, so keep going until at least 10 December if the bracts have not coloured. Penn State keeps the routine until about Thanksgiving (25 November 2027). (Clemson HGIC 1561; Penn State, poinsettias)

  6. : Colour shows

    Penn State expects colour on the bracts in early to mid-December; Iowa State and Illinois keep the dark nights going until the bracts colour well. Then enjoy it in a bright spot. (Penn State, poinsettias; Iowa State, poinsettias; Illinois Extension, houseplant FAQ)

From the shop to January

The trip home. University of Minnesota Extension and Clemson both put the danger line at 10°C (50°F): below it poinsettias suffer chilling injury and drop leaves early. Illinois Extension says to have it sleeved or covered whenever it is colder than that outside, because even a few minutes of cold can damage the bracts and leaves. Penn State bags it in wind as well, and Iowa State warns that freezing, even for a moment, blackens the leaves. Go straight to a warmed car and straight home. Buying one for Thanksgiving (Thursday 26 November 2026) or Christmas? Check the outdoor temperature in the tool above before you set off.

Light and warmth. Give it at least 6 hours of bright, indirect light a day (Clemson, Penn State) and a room at 18 to 21°C (65 to 70°F), ideally a little cooler at night, around 13°C (55°F) (Minnesota, Illinois, Penn State). Keep it away from cold draughts, heating vents, fireplaces and space heaters.

Water. Water when the surface feels dry to a light touch, or the pot feels light when lifted (Minnesota). Take it out of the decorative foil first or punch holes in the foil so water can drain, and never leave it standing in water (Illinois, Maryland).

Feeding. None while it is in bloom (Clemson, Minnesota). With good care, Illinois says it lasts 6 to 8 weeks.

Is a poinsettia toxic to cats and dogs?

Mildly. The ASPCA lists poinsettia as toxic to dogs, cats and horses, with an irritant sap, and describes the signs as irritating to the mouth and stomach, sometimes causing vomiting, but generally over-rated in toxicity. Pet Poison Helpline calls it only mildly toxic to cats and dogs. The milky sap can also irritate skin (University of Minnesota Extension, NC State). Keep it where pets cannot chew it, and if one does, call your vet or a pet poison helpline.

For people, the reputation is a myth. Illinois Extension reports a study of 22,793 poinsettia exposures reported to US poison control centres in which 96.1% of people were not treated in a health care facility, and Iowa State notes there were no deaths. Illinois also cites Ohio State rat tests that found no ill effects. It is still not food: if a child eats some and seems unwell, call your doctor or local poison control centre.

Making it colour again

Poinsettias colour up in response to long nights, so the plant you keep needs an autumn of uninterrupted darkness. The calendar above lays out the year: cut back in spring, repot in early June, pinch the tips through summer but not after 1 September, and start long nights about 1 October.

midnight noon 14 h dark 10 h light Dark: 5 p.m. to 7 a.m. (17:00 to 07:00), every night from about 1 October, for 8 to 10 weeks
The nightly routine for 14 hours of darkness: a closet or a box over the plant from 5 p.m. to 7 a.m., then 6 to 8 hours of bright sun by day (Maryland Extension, Clemson). Even a small light leak can prevent flowering (Maryland Extension).

The sources agree on long nights from about the start of October but differ on details. Darkness: 14 hours (Clemson, Penn State, Maryland), 5 p.m. to 8 a.m., which is 15 hours (Iowa State, Illinois), or 16 hours with 8 of light (Minnesota, NC State). Start: about 1 October (Penn State, Illinois), the first week of October (Clemson), or as early as 21 September (Minnesota). Finish: after 8 to 10 weeks (Clemson), about Thanksgiving (Penn State), or once the bracts colour well, usually early to mid-December (Iowa State, Illinois). Keep nights at 16 to 21°C (60 to 70°F); Illinois warns that nights above 21 to 24°C (70 to 75°F) can delay or prevent flowering.

A worked example: colour for Christmas 2027

Long nights start on Friday 1 October 2027. Eight weeks takes you to Friday 26 November 2027, the day after US Thanksgiving (Thursday 25 November 2027); ten weeks to Friday 10 December 2027. Penn State expects colour on the bracts in early to mid-December.

Common mistakes

  • Leaving it in the foil sleeve, so water pools round the roots.
  • A shopping trip with the plant in a cold car. A few minutes of cold can damage it (Illinois).
  • A spot by the fireplace or heating vent, which Minnesota and Clemson both warn against.
  • Light leaks during the long nights: a lamp switched on in the room or a gap in the box can stop flowering (Maryland).
  • Pinching after 1 September, which leaves too little time for flowers to form (Penn State).

General information from the extension and animal poison control pages listed below, not medical or veterinary advice.

Frequently asked questions

Is a poinsettia toxic to cats?

Mildly. The ASPCA lists it as toxic to cats, dogs and horses but generally over-rated in toxicity: it irritates the mouth and stomach and sometimes causes vomiting. Pet Poison Helpline calls it only mildly toxic. Call your vet if your cat chews one.

How do I keep a poinsettia alive until Christmas?

Wrap it for the trip home if it is below 10°C (50°F), then give it at least 6 hours of bright, indirect light, 18 to 21°C (65 to 70°F), water when the surface feels dry, no standing water and no fertiliser.

Why is my poinsettia dropping its leaves?

Usually cold: Clemson says chilling below 10°C (50°F) causes premature leaf drop, and draughts from doors or vents add to it. Sitting in water in its foil sleeve is the other common cause.

How do I make my poinsettia turn red again?

Give it 14 hours of complete darkness every night from about 1 October, with 6 to 8 hours of bright sun by day, for 8 to 10 weeks (Clemson, Penn State). Colour usually shows in early to mid-December.

When should I cut back my poinsettia?

When the bracts fade in March or April, cut it back to about 20 cm (8 in) (Clemson). Illinois waits for new growth in early May and cuts to 10 to 15 cm (4 to 6 in).

Sources

All opened and checked on 3 November 2026. Temperatures in °C are converted from the sources’ °F figures.

  1. Growing and caring for poinsettia. University of Minnesota Extension, reviewed 2026.
  2. Poinsettia (HGIC 1561). Clemson Cooperative Extension, Home & Garden Information Center, revised 20 December 2015.
  3. Poinsettias. Penn State Extension Master Gardener Program, 31 January 2023.
  4. Guide to Selection and Care of Poinsettias. Iowa State University Extension and Outreach, reviewed November 2025.
  5. Caring for Poinsettias. University of Illinois Extension.
  6. Houseplants: Frequently Asked Questions. University of Illinois Extension.
  7. Poinsettias. University of Maryland Extension, updated 12 December 2023.
  8. Euphorbia pulcherrima (Plant Toolbox). NC State Extension.
  9. Poinsettia. ASPCA Animal Poison Control.
  10. Poinsettia. Pet Poison Helpline.
  11. Federal Holidays. U.S. Office of Personnel Management.