How are these shots made?

[JBPhotog]

I don't think so.

Have a closer look, there are no distinct shadows in the "sanctuary" photo. Then compare them with the shadows in your 'flash' shot, shadows are quite distinct. Additionally, the ISL has compressed the falloff in your photo and rapid loss of light is noticed as the subject matter gets farther away from the flash. The opposite is true with the "sanctuary" photo and if flash was used(I doubt it) it would have to be large and quite far away from the top most subject matter due to ISL.

Did you shoot one without flash?

 

[tirediron]

Whether he used flash or did it all in software is hard to say, but if you look at 'Sanctuary' there is, in my view, a distinct similarity to the OPs image in that the "top" row of ferns in 'Sanctuary' is at least 2/3 - 1 stop brighter than the clover, etc, six or so inches lower. I had initially postulated that he may have used a ring light, but Derrel's suggestion of a large SB makes even more sense.

 

[Derrel]

The ISL is the Inverse Square Law....if you move your flash to 10' or farther, the rate of fall-off is fairly minimimal...the closer the flash to the subject, the greater the rate of light fall-off.