My game only crashes about 50% of the time with Spike Growth - but I do see near catastrophic lag times with it.

Mind you, it was dealing out HUGE amounts of damage, so I went right ahead and cast it again the next time I tried the fights where the game went down. I'm not sure it's supposed to be doing upwards of 40 points of damage, but it makes Meleny feel useful, so I'm not complaining.
I only saw this once the new patch was installed, but I hadn't cast SG before that, so I can't confirm when this error came in.