Poinsettia Warm Climate Production Guidelines
Commercial Production Guidelines /Landscape Culture Requirements
Common Name: Poinsettia
Scientific Name: Euphorbia pulcherrima
Family Name: Euphorbiaceae
General Information
about the crop:
Tropical evergreen, semi evergreen, or deciduous shrub, leggy to 10 feet or
taller. Coarse leaves on upright canes. Inconspicuous flowers, but has showy
petal-like bracts in shades of red, white, pink, coral, and purple tones,
or combinations of these colors.
In truly tropical areas the plant can be adapted outdoors as a shrub or informal
hedge, but in almost all cases is grown as a flowering indoor plant for the
winter holiday season.
Plants per pot:
Usually 1 cutting per 4" or 6" pot. 1-3 cuttings in 8"-10"
containers, or hanging baskets. Specialty crops in larger pots may require
3-5 cuttings per pot. A broad spectrum fungicide is recommended at 1 week
after planting to reduce chances of disease problems during the early phases
of production.
Media pH preference:
5.5-6.5, Dolomite lime preferred for media pH control. Note: poinsettias prefer
a more acidic media than many other flowering potted crops, care should be
taken to keep pH within the preferred range.
Production Light levels:
Under most Florida conditions a 30% level (compared to full sun production)
is recommended, but this varies depending on the greenhouse used for production
and the amount of light that passes through the covering. Higher light decreases
plant height and increases bract color, and light less than 5000 fc is detrimental
to growth.
Production temperatures:
Day temperatures can vary between 75-80°F.
Night temperatures should remain above 60F throughout production.
Poinsettia crops are delayed when night temperatures drop below 50F. Once
bracts are fully formed, many growers drop temperatures to 50F at night to
intensify bract coloration.
Fertilization:
Fertilizer concentration should be maintained at 200- 300 ppm N for constant
fertilization, and 400-500 ppm when fertilizing intermittently every 7-10
days.
Fertilizer formulation is somewhat flexible but most Florida growers use either
a 20-10-20 formulation or 15-5-15 formulation. In all cases the fertilizer
should have high calcium and magnesium levels to avoid problems with bract
edge burn at finish. Fertilizer needs also differ from variety to variety.
A complete micronutrient application is recommended at 1-2 weeks after planting
rooted cuttings.
Propagation:
Many growers opt for purchasing rooted cuttings of this crop rather than propagating
their own plants, as sanitation when cuttings are taken is critical to producing
good finshed plants.
For growers producing their own cuttings: Root cuttings in a sterile, porous
medium and keep cutting equipment and cutting area clean and sterile to prevent
disease. Maintain temperatures between 70-75°F with100% humidity as cuttings
begin rooting, and then lower humidity as roots develop. For direct stick,
overwatering should be avoided to prevent rotting.
Pinching required:
Pinch to seven nodes at approximately 2-3 weeks after planting; the first
pinch should be removal of .5 to 1" of the top growth, if plants are
allowed to grow larger before pinching crop delays can result.
If a grower is harvesting cuttings from plants while pinching, the pinch should
be delayed until 3-4 weeks after planting.
Plant Growth Regulator
(PGR) recommendations:
There are many successful ways to control poinsettia height under warm climate
production. Depending on the grower's equipment and labor there are two main
ways to apply PGRs: 1. Spray applications - are the lowest labor but can complicate
quality production if applied too late in the crop cycle, 2. Drench applications
- where a PGR solution is applied to the soil, offer the most uniform results
with fewer problems, but require more labor investment in many cases. For
more information on PGRs and poinsettia production click
here.
Photoperiod:
Poinsettia is what is a called a short day photoperiod crop, which means that
it naturally flowers when the nights become longer than the days. In commercial
production many growers use black cloth to either produce earlier crops or
make the entire crop more uniform. However, recent advances in breeding have
led to crops which flower naturally early enough in the season to meet early
sales requirements.
There are currently over 100 Poinsettia hybrids on the market, and selecting
the correct hybrid for your production needs is one of the biggest decisions
in this crop.
Scheduling:
Rooted cuttings should be planted beginning in mid August. Planting can continue
up to September 1st for late crops, however the early market is where most
sales occur and the late market can be much chancier for growers. Critical
Dates should be determined based on each pot size and variety.
Common Production
Problems:
Poinsettia hornworm, fungus gnats, spider mites, beet armyworm, whitefly,
scale, various fungal diseases, Botrytis, root and stem rot, bacterial canker
Recommended Cultivars for Southern US: click here for a printable chart of recommended cultivars
Light levels:
Full sun to partial shade
Water requirements:
Lightly moist to somewhat dry.
Fertilization:
A balanced slow release fertilizer, with full micronutrient array. Should
be applied spring through summer but reduce fertilizer in mid to late summer
for best flowering.
Season of interest:
Early fall into winter in frost free areas.
Common Problems:
Many people plant poinsettias where there is a night/street light which lights
the plant after sun down. This delays flowering and reduces color, and so
should be avoided. It takes at least 8 weeks of short day conditions to get
a landscape poinsettia into flower, for this reason using poinsettias in the
landsacape (or reflowering them indoors) is usually more work than it is worth.
Poinsettias are extremely frost sensitive and will die back or stop developing
at 40F, this also limits their use in the Florida landscape.
Consumer / Postharvest
information:
For information
on maximizing the life of your poinsettia please check the following resources:
Ecke Ranch hyperlink
SAF hyperlink