Tyne And Wear,
United Kingdom 
hi all have a pampas grass in a large pot but it never seems to have many plumes on it only one this year does anyone know how to get more plumes as i have seen in some gardens is it because it is restricted in a large pot ? thanks owen
25 Oct, 2012
Answers
I can endorse that as they grow wild not far from here - and you should see the monsters - plumes seemingly never less than double figures on each plant!
26 Oct, 2012
What variety of pampas grass, and just how large is the pot, Guitarfingers? A full-sized pampas grass wouldn't do well in a pot less than 1 1/2 meters wide and tall. Dwarf kinds can work in pots down to about 1/2 meter wide and tall, but will require frequent watering and feeding to stay healthy.
27 Oct, 2012
Previous question
I would suspect the fact that it's in a pot is the reason. I don't grow them but I've seen them in enough gardens to know that they get rather large!!
Your solution would be to plant it in the ground in an appropriate spot.
25 Oct, 2012