Chester sightings & buddleia question

[ButterflyPR at comcast.net]

Lots of activity around the buddleia yesterday.
Two male monarchs, one trying to chase the other away.  Also saw a female earlier, in a nearby tree, checking out the milkweed patch.
one Tiger Swallowtail
two different clearwing moths (possibly one bumblebee and one hummingbird?)
one Silver Spotted Skipper
at least two other skippers, fairly certain one was a Peck's, other might have been Little Glassywing
Also, not actually seen in the buddleia, but flying by and landing on the grass, a Buckeye--the first I've ever seen in my yard :-)

Buddleia question--I've always just let it go to seed, but it's looking really healthy this year, and I'd like to keep it that way as long as possible.  Can someone please tell me about deadheading--when to do it, exactly what to do (where to cut?)

Thanks!
Diane
in Chester