"Scopata Fuori" wrote in message
...

It sounds as though they are getting too much nitrogen, and not enough
phosphorous. Some folks would say to cut back on the nitrogen, but in my
experience, if you're getting lots of leaves, that's half the battle right
there. It's obviously healthy. And if it was an actual overdose of
nitrogen
it would be damaging the plant, as it will burn in too high
concentrations.
Get some low nitrogen fertilizer, with plenty of phosphorous, and I think
you'll see a difference.

snip

Consider using bone meal, which lasts a long time and provides a steady
supply of phosphorous. Unfortunately it's best if you can spread the stuff
in the ground near the roots, rather then sprinkling around the surface. If
you can get rock phosphorous add that too, but it is critical that it be
placed under the surface of the soil.

In a jiffy, you could use Miracle-Gro, make a dilute solution, put it in a
spray bottle and mist the leaves on a sunny morning, and water the plant
with a normal concentration of the stuff. But it's not really a long term
solution.

Good luck
Sameer