Rex begonia 'Silver Queen'. It can be grown outdoors after danger of frost has passed like most begonias. It often defoliates in winter indoors.

Often colder temps bring on the color changes to pink. Here is one of mine in October 2010

Posted by hcmcdole z7 (hcmcdole@bellsouth.net) on Mon, Aug 5, 13 at 17:47

Wow, you have so many wonderful begonias! Your silver queen is beautiful:) I must have one soon.

One question:

The begonia in the first post appears to have the same pattern on leaves. However, the begonia in the first post seems to have metallic (reflex light like tinfoil) green parts. In comparison, the corresponding green parts of silver queen seem to be not metallic.

The plant in the first post also appears to be extremely large with larger leaves. Hmm ... I am just wondering.

I do believe the first picture was taken with a flash which will cause some of the reflections (also light up some areas of begonias that appear blue). The first one may be bigger but hard to tell without some kind of "yardstick". I still believe it is 'Silver Queen'. Here is what it looked like in warmer temps. The lens cap is 72 mm (about 3 inches) for comparison.

Posted by hcmcdole z7 (hcmcdole@bellsouth.net) on Tue, Aug 6, 13 at 10:53

I see. Wow, your silver queen is big and great!

Would you share some caring tips :) ... like potting material, temperature and how to water ...

Nothing too magical about care. I use Miracle Gro potting mix but any good quality mix will do you fine. Indoors I grow under shop lights just to keep them happy during winter. In summer I move them out to a semi-shady location and keep them watered. Even during this summer of lots of rain, pots dry out faster than the ground so watering may be a daily occurrence. I don't fertilize religiously in summer but new potting soil with slow release granules helps tremendously. The biggest thing I have to watch for is a clogged drainage hole when water is standing in the pot - this must be corrected as soon as it is noticed else the plant may start rotting very early.

Posted by hcmcdole z7 (hcmcdole@bellsouth.net) on Tue, Aug 6, 13 at 16:48

I bought a few before. The soil in pot never dried out and the plant was simply not growing. They appeared to have root rot and root dry-out intermittently. They never grew new leaf successfully. They always decline and die :( Of course, the climate was very dry and hot. The water was salt-softened. The soil was not sterile, and filled with active fungus, etc.