work-out to improve hill climbing?

not to be snarky, but take your bike outside, and ride hills. thats how you get better at hills

Noticed you were trying to replicate out of the saddle riding. Are you having to stand for every single hill?

Best thing for me is just becoming a stronger rider, and a lot of that work has come on the trainer. Really figure out what working hard is and learn various types of intervals to improve your cycling power (also not intending to sound snarky here). The stronger you get the more the hills just take care of themselves.

x2.  For triathlon riding, it's simply about improving bike fitness, reducing as much weight (off you and/or your bike), pacing, and proper gearing.  There really is nothing special about hills you need to train for unless you're tackling something really steep...which most triathlon courses avoid.  Hills are great for training, but really not that different from simply using your trainer assuming you force yourself to ride at higher intensity like a hill would.

Can you get in intervals of 8-20 minutes in length? Try to do enough to total 30-40 minutes of going hard, and do about 20-25% of the work part for recovery. Most use nice number like 8, 10, 12, 15 and 20 for the hard parts. Because of the increased duration (both interval length and workout total) you won't be able to work at quite the same intensity as the shorter ones you're now doing, but that's ok. Stay strong throughout and you can still be very spent at the end. The hurt will come a little bit later than you're used to. So these would be 4-5 x 8' w/2' recoveries, or 2 x 20' w/4' recovery. I tend to do well with performing several of these workouts for every one of the workouts you're doing now, the 3-4 minutes of work with about equal rest.

Did you have anything to monitor effort? Such as power or heart rate? Do you have trainer speed? What you're trying to do with this is figure out a fairly consistent output throughout each interval and from interval to interval. These can help guide you to that as perceived effort can be misleading.

In addition to brigby's advice on the intervals, unless you are training for rowing or climbing stairs, ditch the 20min on the rowing machine and stairmaster and add that time to the biking.  As noted, there is no big secret training for the hills.  Ride more.  And ride harder, at times.  You'll eventually ride faster on hills or flats.

Only you know the answer to that question.  I'm just pointing out that climbing is very much just a power to weight equation.  There is no real "skill" involved in climbing with regards to triathlon.  Do the things that will help increase your power (intervals, volume, etc.), do the things that will help you get to or maintain your ideal weight...and you will climb better.

I think there is some skill when it comes to hill climbing - and hills is a subjective term based on where you live.  For me, a long steady gradient is great and I do well, but for shorter steeper hills that require a punchier effort I either get blown out near the bottom, or I blow up trying to keep up and then need to recover.  Even after 6+ years I still find myself having to manage my power up hills and then chasing to make up the time I lost. 

Which would go back to my earlier comment about proper gearing and proper pacing.  And again, this is in terms of triathlon where you are just riding your own race...not trying to keep up with a pack who may be *attacking* the hills.  Also in terms of triathlon in the sense that most courses don't include steep sections that require you to do anything different skill wise assuming you have enough gearing.

Right, "no real skill" doesn't literally mean zero, just that's it's fairly low. Also, if you goof it up it can make you pay, but that still doesn't mean it takes a lot of skill to manage. Anticipate how the upcoming terrain will affect the gear selection. 

I think we're talking different things here a little - gear selection, how to approach the hill, etc., are all things I feel I have a pretty good handle on.  W/kg (To leego's comment) are ok, but I feel one has to practice hard, short hill efforts so you get used to pushing those above threshold efforts, and then return to just below threshold in a race, rather than having to recover before you resume the effort again.  At the same time, how you approach a longer more consistent climb is again going to be different.

To Jason's comment, in a shorter race I don't feel like you're riding your own race  all the time, you're aware of those who you have passed or have passed you and you can choose to alter your effort to keep pace or let them go.  I just find that people put out a lot more effort on those shorter hills and ride off - perhaps I have fewer matches, or I just don't burn as many on the hills

Perhaps you could expand on the "hard, short" parts as what I'm reading doesn't really sound like how I've raced. Power may not stay perfectly flat, but I'm not going way past threshold either. Even with short course racing. How hard do you think these guys are going?