Achimenes for this year

It seems my planting area is too tough to grow Achimenes, I try again this year and I do not like the growing result so far. The Achimenes plants sometimes seem exhausted because the summer is too hot and the sun light is too strong. Therefore they are not well developed before the bloom season, that's why I see only a few flowers, the worst is some even do not bloom but go into dormancy on the contrary. Well ... at least I tried.  :-)