I grow mostly large poinsettia pots, 10", with a height spec of 24-26". I sandwich the pinch with a florel spray of 400 ppm. It really seems to make the crop very even in growth, but it works as a PGR too much. I am forced to use fascination and/or a positive DIF to stay on my growth curve. Can I get the same "florel response" at a lower rate for these large pots?

Deke -

The response you get with Florel will vary depending on the container size you are growing in, the cultivar and environmental conditions in the greenhouse at the time. Florel does have some growth regulating effects but typically they are mild compared to other growth regulators available. If you are having trouble reaching your desired finished height it may be that you need to evaluate your pinch dates also. A typical schedule for a medium vigor cultivar (Prestige or Freedom for example) in a 10" container in a central location needs about 40 days of vegetative growth between pinch and flower initiation to achieve your desired height. The vegetative phase would be shorter in a southern location and longer in the north. The vigor of a particular cultivar will also change the pinch date.

The labeled rates for Florel are 250-500 ppm. Typically you would use higher rates for cultivars that don't naturally branch well, such as Winter Rose. Cultivars that branch well on their own will respond to the lower rates (250-300 ppm) but won't have as much of a growth regulating effect.

Hope this helps. Let us know if you have more questions!