Difficult to think of a true blue flower, other than a few, and Alliums are not on my list. All seem a blue shade of violet, and my camera does not report them faithfully. I call some Gentians true blue, Forget Me Not, and Heavenly Blue Morning Glory, but not too many more. Some catalogs are notorious for inaccurate coloring.

This will grow in zone 6? I'm 6b... I haven't seen passion flower around here before! Actually, I've never seen one in real life. I just updated me have/want list today. Are these hard to root? Do they take any special care?

^Correct. I have that one, it spreads fairly aggressively but can be pulled out. There are more showy gentians out there but this one is very hardy.

I like blue and use it a lot - in the garden; in the house; in my wardrobe... but I've never felt the need to pursue 'true' blue - if it's reasonably blue, I'll likely be happy with it :-) Color preferences are definitely a personal thing, although it does change over time I've found. In general, these days I prefer cool colors more than 'hot' ones. I do like pink - but mainly the cooler shades of pink. And I prefer to use large quantities of a color - I'm drawn for some reason to monochrome type color schemes where the planting includes variations of a limited number of colors. Sometimes though the introduction of an unexpected color can be just what's needed. Gardengal- orange is one of those colors that I don't normally use but I particularly like the spring scene out the window of my home office. The squirrels obviously raided a neighbour's tulip bed and added their booty to my garden! I wouldn't have planted these tulips myself but I love the combination and, luckily, it has been coming back for at least 5 years now! Without the orange, this would be a rather dull scene...: Another accidental orange combination I really like is this one of some of those cursed ditch daylilies that came with the house plus the next-door-neighbour's Jackmani (?) clematis tumbling over the fence. I like it so much that I have refrained from ripping out the ditch daylilies (that are otherwise a PITA!) I seem to have strayed off topic somewhat here but I really like playing with color and am always looking for color combinations/ideas to adopt. How do you use orange gardengal - i.e. what are some of your favorite orange scenes?