Andrew I am using the Lightning Trigger seen
http://www.lightningtrigger.com/
During the day light shots I use the trigger and then during the night shots I also use it but set the camera to 20" on manual and let the trigger start the exposure. It is very effective on reducing the actuations (already up to 40000 actuations).
For daylight stuff I just follow the tips from the site on settings and this works quite well. Although I tend to use a higher ISO to capture more. The Geranium shot I produced over 300 actuations and none showed lightning but I could clearly see c-c lightning lighting up the clouds. Interesting to watch but not productive. I was hoping for that setting to see a ground strike and that would have made my year just for that shot with all that lovely colour in the rain.
Thanks for the comments guys.