At minimum--minimum--keep the roses outside of the "drip line" of the tree at its mature size. The "drip line" is the imaginary line that comes straight down vertically from the outer perimeter of the MATURE size of the tree. Say the mature width of the river birch is estimated to be 12' (I don't know what the mature width is). Then you would plant roses no closer than 6' from the trunk. Eventually the roses may decline, but in zone 6 winter may kill them off before the tree does.

Roses do not have particularly robust root systems, especially in comparison to trees. They just can't compete well. If you try to compensate by giving the roses extra water, the tree roots sensing the presence of water, will move in the roses direction.

Good luck with your project! Nothing wrong with Knock Outs, they are roses too! :)

I'm the proud owner of a river birch that's about forty feet tall. It is surrounded by pink azaleas: nice in spring, boring for the rest of the year. Anyway, the birch has surface roots spreading out into the lawn similar to a silver maple. Its challenging to mow the grass due to the large roots mounding up above soil level. The large roots extend at least twice the width of the tree. When I tuck vinca into the bed around the azaleas each May, there is a thick network of surface roots that I must cut through. I can't imagine roses thriving anywhere near a river birch. Sorry.

Yikes cecily! I acctually also have a silver maple in a pot (I rescued it from a friend who got it as a housewarming gift and wanted no part of it) and have left it in a huge conainer for the reasons you explain. I Never knew birches were so troublesome-they seem so innocent!!!

Hmm..the other place I could stick it is in the front lawn and have a huge mulch bed around it. I actually hate lawn, so I' welcome any chance to rip some of it out. I 've also heard river birches are very messy.

But they are so beautiful!

My knockouts are the ONLY failproof thing in my yard, so i'll do whatever i can to keep themhappy, which means no tree. Beetle infestations, month long drought and water ban, hungry bunnies and deer...all have ravished my yard and reaked havock on my garden--even the "easy to grow" stuff. My knockouts haven't looked anything less than spectacular not for a singleday.

I agree with all posters on the problems with birches, not that we have river birches here, our variety is Betula pendula. They are the thirstiest trees after salixes over here and stump the growth of roses significantly. Rugosas and Rosa californica Plena have been the only roses to do reasonably well near the neighbours' five tall birches but outside their drip line. Even spinosissimas suffer and we had to remove several dogwoods. But you could put in a barrier of some sort against the roots.

Yes, many rosarians dig up lawn away from trees to plant roses--if you have a nice area of lawn this is a good spot for roses, once the grass is removed. If you absolutely have to have roses near trees, you might try vigorous gallicas like La Belle Sultane--they are great roses for our New England climate.