Poinsettia Production Guidelines
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.
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.
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.
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 finished 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.
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:
- Spray applications - are the lowest labor but can complicate quality production if applied too late in the crop cycle.
- 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.
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.
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
Full sun to partial shade
Lightly moist to somewhat dry.
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.
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 landscape (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
Please visit Ecke Ranch.