I have a path that is pea gravel and one of my spreading plants that flowers jumped into my path and it has spread about 2 ft by 2ft. it looks beautiful when it flowers. So depending on the plants you planted it should be no problem.
It does depend on the plant. The pea gravel will work as a mulch holding in water, deterring weeds, but it will hold and release more heat than barks, straw, etc. If you have a heat loving plant you are good, if it can’t take the heat, you will have a wilter. Happy Gardening
I have used pea gravel and little big larger rocks (river rock?) around my beds mixing a large stone here or there. I give each of my plants at least 10 inches around base of them so they have some breathing room and the rocks don’t crush any new growth.
My grandma used to mulch her flower beds with red landscaping rock and would use old coffee cans with bottoms cut off and would place round base pushed into soil(Leaving a 2 inch lip sticking out of soil)These would go around her impatiens so rocks wouldn’t crush them. It worked perfectly.
no the roots will make their way to dirt
No sorry… I have tried.. I think it helps them spread faster 
the only thing is its easier to pull them.
Will be interesting to see what others have to say… looking for ideas as well.
it might be too heavy for the plants to sprout out from it.but waite and see you might not have any problem at all.just i have never heard of using pea gravel instead of mulch i guess there is a first for everything it is a good idear though i bet if the flowers come up it looks real pretty.i hope you did not put on a thick layer of the pea gravel.just to be sure it is not to heavy for the flowers.