CULTURE OF STREPTOCARPUS

Streps like the same conditions as African violets, except:

1. A little more light.

2. More alkaline soil (soil that is closer to neutral, rather than 
slightly acid).

3. A looser soil mix (see below).

4.  COOLER TEMPERATURES.  Ideal is roughly 55(F) to roughly 72. 
In temps over about 80-85, streps will wilt even if the roots 
have plenty of water.  This is deceptive, because it looks as though
the plant needs water, but it doesn't - it's just heat stress.  
You can tell that this is happening because, even though you 
didn't water the plant, its leaves firm back up at night, when the 
temperature cools down.  

If you overwater streps during hot weather they will die.  

However, they can handle some heat; mine are seldom below 80 
in summer and do fine. 
The key is to have a coarse, loose soil mix, so the roots get 
plenty of air.  Half perlite is not too light, although it 
needs frequent watering.  Clay pots also help.
Or, of course, you can just put your streps in a cool room :-).

5. If you can keep them cool streps are easy to grow.

Streps can be started from leaves.  Cut the leaf in half and
stick any part of it into rooting mix.  It's weird.