Bark mulch as weed control

Last year I laid decorative chipped bark in an area of the garden holding a large variety of perennials, as a method of keeping down the weeds.
This year so far,I have noticed that quite a few plants such as columbine, primula and poppy have not appeared and seem to have died off.
Could this have been as a result of something in the bark or the type of bark I used. Has anyone else experienced this problem.

 

Hm, I don't think so - I used chipped bark on the beds in the front garden (pansies), left the pansies in there over winter and some came back easy this spring, I did not want them this year though and just last thursday cleaned out the bed, and the bark had composted nicely into the soil - best soil in the house! No need for extra compost this spring when I planted my lobelias there!
I can't really imagine the bark mulch killing off plants...

 

I have used bark mulch for 2 or 3 years without any problem. However it does its job very efficiently and stops things self seeding. Some plants are short lived and it is the self seeding that keeps the line going. But that is stopped with a thick mulch.