I do not know the exact reason, but in Gwalior climate only the pink one survives. White and red are probably not able to tolerate the dry heat of Gwalior.
Anand Kumar Bhatt
A-59, B.S.F.Colony, Airport Road
Gwalior. 474 005.
Tele: 0751-247 2233. Mobile 0 94253 09780.
My blogsite is at:http://anandkbhatt.blogspot.com
(A new blogs has been added on 30 May 10.)
And the photo site:www.flickr.com/photos/akbhatt/
Ten most common surnames of Indians: Singh, Kumar, Sharma, Patel, Shah, Lal, Gupta, Bhat, Rao, Reddy. Cheers!