E-Letter 1

In an effort to support growers throughout the year, we will be emailing periodic messages to all who are using our new Tech Help email system. We hope you find these crop reminders and culture alerts worthwhile. Information on a range of topics will be sent based on the questions we are receiving or anticipate from growers. We look forward to your feedback regarding this service!

This year’s drought has affected many water supplies, impacting mineral content, pH and EC from previous years. If you have not already had a new water test done to see if adjustments to your current fertilizer program are needed, get one.

By now, young poinsettias should all be established and pinched. Small pots are still within normal pinch schedules, but for growers in northern states, we expect that all pinching should be complete.

The late Thanksgiving (28 November) may influence delivery dates this year (be sure to confirm with your customers), so now is the time to take control of crop timing. Lights can be used beginning now to assure poinsettias do not initiate early in response to shorter days and cloudy, cool conditions. Night interruption lighting requires a minimum of 10 ftcdl / 100 lux at plant height. Cyclic lighting programs are acceptable with the interruption cycle starting at 10:00 PM and continuing until 2:00 AM. Use daily until an appropriate initiation date is reached (for example, if Freedom needs to mature on 20 November, discontinue lights no later than 25 September). As a caution, response times get longer than stated if production temperatures are reduced or if late crops are grown without normal heat to compensate for shorter, darker days of November/December.

Fertilization practices should be monitored and adjusted as the crop develops. As new shoots form, rapid plant growth requires increased fertilizer levels to assure optimum development. Avoid extremes of low or high fertility levels, and supply a balanced feed program to support growth. Include a regular supply of calcium and supplement with STEM or other trace elements monthly. Periodic soil and tissue analysis is the best way to keep nutrition on track.

Now is the time to increase light intensities. Shade is effective at reducing greenhouse temperatures, but high light builds stronger, thicker shoots and reduces the risk of stem breakage during shipping. While adjusting to higher light, mitigate heat stress whenever leaves become warm to the touch. This situation is unlikely to be long-term unless you are located in the Southern regions. High light (5000+ ftcdl 50000+ lux) during Sept/Oct encourages thicker caliper stems, reducing need for plant growth regulators and facilitating quicker drying of media, allowing more frequent irrigation and fertilization.

Graphical tracking should be used to help growers make decisions regarding use of cultural practices or plant growth regulators (PGR’s) to manage stretch. A free copy of the current program can be downloaded at www.ecke.com.