[AG-EQ] How to care for your poinsettia

[dogwood farm]

Poinsettia Plant Profile
By Marie Iannotti
Marie Iannotti is an author, photographer, and speaker with 27 years
of experience as a Cornell Cooperative Extension Horticulture Educator
and Master Gardener

 In This Article:
How to Grow
Light
Soil
Water
Temperature and Humidity
Fertilizer
Potting
Varieties
Toxicity

Poinsettia plants (Euphorbia pulcherrima) remain one of the most
popular holiday flowers. The familiar red blooms have been joined by
even flashier colors. Actually, they are not flowers but modified
leaves called bracts. The bright bracts are designed to attract
insects to the tiny yellow flowers in their centers. Hybridizers have
expanded the range of colors from the familiar red to pastel yellow
and vibrant bicolors. Because poinsettias have been forced into bloom,
they need some extra care to keep them in bloom throughout the
holidays. While it may be easier to buy new plants each year, it is
possible to get them to rebloom the next season.

Botanical Name Euphorbia pulcherrima
Common Name Poinsettia
Plant Type Perennial shrub
Mature Size Two feet
Sun Exposure Full sun
Soil Type Loamy
Soil pH 5.5 to 6.5
Bloom Time Winter
Flower Color Yellow
Hardiness Zones 10, 11, and 12
Native Area Tropical forests of Mexico

You can keep your poinsettia healthy and vigorous throughout the
holiday season with the right care. Give them enough sun, warmth, and
water and your poinsettia will provide perfect seasonal color. If you
want to save your poinsettia and bring it to bloom again next year,
you can follow the repotting and reblooming procedure.

 Light

Place the poinsettia near a sunny window. South-, east- or west-facing
windows are preferable to a north-facing window. Poinsettias are
tropicals and will appreciate as much direct sunlight as you can
provide.

 Soil

A loose, well-draining peat-based potting soil is best for your poinsettia.

Water

Water the plant whenever the surface feels dry to the touch. Water
until it drains out the bottom, but do not let the plant sit in water.
Wilting is a common cause of leaf drop. A wilted plant can be revived
and salvaged, but it will take another season to improve its
appearance.

Temperature and Humidity

To keep the poinsettia in bloom as long as possible, maintain a
temperature of 65 to 75 F during the day. Dropping the temperature to
about 60 F at night will not hurt the plant. However, cold drafts or
allowing the leaves to touch a cold window can injure the leaves and
cause premature leaf drop. If you've ever seen a leggy poinsettia in
bloom, with only a couple of sad looking leaves hanging on, it was
probably exposed to temperatures that were too cool or to extreme
shifts in temperature.

Lack of humidity during dry seasons, in particular, winter, is an
ongoing houseplant problem. If your home tends to be dry and your
poinsettia is in direct light, you will find yourself watering
frequently, possibly every day.

Fertilizer

Do not fertilize poinsettias during the blooming period. When keeping
the plant through the year, begin fertilizing in the spring every
three to four weeks with half-strength fertilizer.

Potting and Repotting

If you wish to keep your poinsettia through more than one season and
force reblooming, follow these steps. Getting a poinsettia to rebloom
is not an easy process, so don't be disheartened if you don't have
success your first try.

1. January to March: Keep watering the poinsettia whenever the surface is dry.
2. April: Starting April 1, gradually decrease water, allowing the
soil to get dry between waterings. Be careful that the stem does not
begin to shrivel. This is a sign the plant is too stressed and is
dying. In a week or two, when the plant has acclimated to this drying
process, move it to a cool spot, such as the basement or a heated
garage. You want to keep it at about 60 F.
3. May: In mid-May, cut the stems back to about four inches and repot
in a slightly larger container, with new potting soil. Water it well.
Place the newly potted plant back into the brightest window you have
and once again keep it at a temperature of 65 to 75 F. Continue
watering whenever the surface of the soil feels dry. Watch for new
growth. Once new growth appears, begin fertilizing every two weeks
with a complete fertilizer. Follow fertilizer label recommendations.
4. June: Move the poinsettia outside, pot and all. Keep it in a
partially shaded location and maintain your watering and fertilizing
schedule.
5. July: In early July, pinch back each stem by about one inch. This
is to encourage a stout, well-branched plant. If left unpinched, the
poinsettia will grow tall and spindly.
6. August: By mid-August, the stems should have branched and leafed
out. Once again, pinch or cut the new stems, leaving three to four
leaves on each shoot. Bring the plant back indoors and into your
brightest window. Continue watering and fertilizing.
7. September: Continue regular watering and fertilizing. Make sure the
temperature stays above 65 F.
8. October: Poinsettias are short-day plants, meaning their bud set is
affected by the length of daylight. To rebloom, poinsettias need about
10 weeks with 12 hours or less of sunlight per day. You will have to
artificially create these conditions and it's crucial that you be
diligent. Beginning October 1, keep your plant in complete darkness
from 5 p.m. to 8 a.m. Any exposure to light will delay blooming. Use
an opaque box or material to block out light. Many people place their
plants in a closet, but if the light gets in through the cracks or if
you open and use the closet, it will affect the bud set. Move the
plant back to the sunny window during the daytime and continue
watering and fertilizing.
9. November: Around the last week of November, you can stop the
darkness treatment and allow the plant to remain in the window. You
should see flower buds at this point.
10. December: Stop fertilizing about December 15. Keep watering and
treat your plant the way you did when you first brought it home in
bloom. If all has gone well, it should be back in bloom and ready to
begin the process all over again.

Varieties of Poinsettias
Besides the traditional red, you will find different colors to enjoy,
including cream, yellow, and pink. Note that some fancy colors, such
as blue, are produced using dyes and the plant won't bloom again with
the same color of bracts. Look for these varieties:

'Tri-Color' has bracts in red, white, and pink.
'Plum Pudding' is a lovely purple color.
'Prestige Maroon' is a deep maroon.
'Lemon Drop' has yellow bracts.
'Jingle Bells' has red bracts dotted with pink.

Toxicity of Poinsettias
For years, poinsettias have had the bad reputation of being poisonous.
They certainly are not meant to be eaten by humans, pets, or livestock
and ingesting poinsettias would probably cause some stomach upset, as
would eating almost any houseplant. However, poinsettias have
undergone extensive testing and there is no evidence that they are
toxic or unsafe to have in the house. They are also safe to put into
the compost.

A more likely problem to watch out for is contact dermatitis.
Euphorbias, the plant family that includes poinsettias, exude a milky
sap when broken. Think of milkweed, another common Euphorbia. Many
people are sensitive to this sap, which can cause an itchy rash. Be
especially careful not to rub your eyes after touching the plants. To
be safe, wash your hands after handling a poinsettia plant and try to
avoid pinching or pruning them with your hands.

Susan
dogwoodfarm62 at gmail.com