My rose Rose of Sharon is 6 years old and is still about 5' tall... but... I think it has grown in height this year already. It is one of the last things to leaf out each spring, and blooms in late summer ..early fall for me.
My zone is a bit warmer than yours, but we have had several very severe winters lately and I think the weather changes are for the worse in our area.

My 3 year old is about 6 inches tall - only one little branch developed leaves and just recently sprung leaves.

Here's a real kicker - A 10 footer next door is slated for removal so the neighbours can put in a circular drive - they are new owners and I told them about this beauty....they weren't convinced as it hadn't budded out at the time - and are not sure what a rose of sharon is....they said 1/2 of the entire tree was dead - I told them to wait abit longer as it buds out late ...it's budding out on all sides now so I'm hoping they don't shovel prune it down & out. I may have to go over there and get some semihardwood cuttings before it's too late. I keep waking up seeing plants and trees up-ended up in a dumpster, roots high and dry out in the sun....

Hi,

I tried three times to grow a 'Blue Bird' Rose of Sharon that grew successfully at my parents zone 6B home. Now, I didn't realize I was trying to push this particular variety as it's not generally hardy in zone 5A. The third time it went on the south side of the house against a brick wall. It grew marvelously for about 6 years and got about 7 feet tall, 4 feet wide and bloomed abundantly. Then one summer (as you may know it's very late to leaf out) it was toast. I was mortified as I adored this plant. It may have been too close to the foundation and ran out of root space as it was jammed in with other things. Perhaps the winter was too harsh that year. Perhaps I just didn't give it enough water to make it through the winter and early spring.

There are varieties of Rose of Sharon or 'Hybiscus Syriacus' to be technical that are hardy for our area. You may want to go on one of the trade lines and ask for seed (be careful to say USDA zone 4 if you are dealing with someone on the other side of the border), or try local nurseries.

I acquired about 4 seedlings last summer that came from the same original mother plant as my other successful one. They are in various flower beds around my home to see which one will be the hardiest. I know there are other varieties, but I love 'Blue Bird' and I'm cheap.

Good luck,
Mary

A guy down the street from me (Kingston)has two large blue ROS in his front garden. I don't know what variety it is but judging by their size, they are at least 15 years old. They seem to like it there and their progeny are popping up all over the place in his garden. I'm not sure what colour mine will be but it's a transplanted 3 year seedling from a another local pink ROS.

Simon

Wouldn't we love to get our hands on those seeds from your neighbour late this fall. You know he'll have thousands of them!

Last year I tried to get seeds of some blue (really purple) ones, but it seemed those offering them were all from southern Ontario or BC and not acclimatized to "our" climate.

Mary

Help! I have 3 very large (over 6 feet tall) rose of sharon bushes which were on our property when we bought our house almost 3 years ago. The first summer all 3 grew beautifully, but last summer 2 of the bushes did not fully bloom (just over half the bush), and now this summer only one has some leaves (not blooming time yet), and the other has no leaves. Is this bush dead?

I too live in Ottawa...however, originally from the Niagara Region in Southern Ontario. ROS back home are like weeds...they grow anywhere...and HUGE! One winter, I left one bare rooted in a 5 gal pail outside...saw it in the spring with buds so I planted it. To my surprise (or maybe not) it took hold and grew!

I wanted one so much for my yard here in Ottawa but was told it was a 75% chance it would DIE the first year! I was advised to ensure the following... 1) in fall - mulch about a foot up the bush 2) it should be the first to have snow on it...so I would shovel snow onto my plant 3) it should be the last to have snow...so I shovelled snow onto my plant until it all finally melted.

My plant lasted 8 year...when I moved and relocated it...guess it didn't like being moved around in Ottawa.

All that said...there is a way to have a ROS in Ottawa and successfully! Happy gardening!