That is how it is suppose to be. I'm not sure if they'll root so late in a season, but in spring they would of rooted for sure. You are a zone pusher :-))

My Mother winter sowed one thing. Tomatoes, seeds she saved every year from her best tomato plants. Sun dried them and saved until late fall early winter. She had an old wash tub filled with sand, garden soil and A little manure from the old pile by the barn, all mixed together. This old tub was leande up against an old oak tree on the north west side of the house where it didn't get much direct sunlight This she would work up and scatter couple hundred seeds and cover them with more sand and forget them. This was in the hills of north west arkansas which I think is still zone 5. Anyhow come spring they would come up and if it was going to be really cold they might get a couple of burlap bags tossed ovwer them, however mostly they survived on their own, And she always had plants for ourselves and to give away also.This was my first experience with winter sowing and I didn't even realize it until I seen This web site. This was over 60 + years ago and this was the way most people did those kind of things. Just reminising over days gone by. So no I don't think you messed up. Mothernature seeds in fall and plants come up in spring and frost doesnt really bother them if done natures way. and as some one said you can always cover them up and it doesn't take anything really heavy. jim

I generally aim for Columbus day so Sept is a little early for you. And trimming off the tops was probably a mistake. Are they sending up new shoots? My guess would be that they are probably OK - I wouldn't pull them out now but you might try digging up a few next month to see if the bulbs are rooting well and, if not, that would be a good time to replant.

If you have heavy clay soil you need to be especially careful about amending planting holes. You run the risk of the potting soil/amended soil retaining too much moisture that does not drain well through the native clay and you wind up with a 'bucket effect' of soggy, poorly draining soil that can be the kiss of death for most plants. Ideally you want to amend as large an area as possible. Rather than amending individual planting holes, amend the entire planting bed. The intent is to make the soil texture as uniform as possible over the largest area and ensure that drainage is relatively prompt. Often with heavy clay or poorly draining soils that is not immediately practical give the size of the area in question or existing established plantings that preclude widespread amending. In that case, it is better to just dig the largest but rather shallow planting hole you can manage, loosening up the existing soil as well as possible. Add no amendments to the hole - existing soil coming out of the hole is the same soil used to refill. The shallow, widely dished planting hole will encourage you to plant high......just mound soil upto to the necessary level, creating a small mound or berm. This will facilitate good drainage yet still accomplish the recommended deep planting routine for clems. If you have insufficient garden soil to make a deep enough mound to cover the rootball and stems, this is where you can augment with some sort of organic amendment, like compost or potting soil/garden mix, etc. It is my experience that clematis - like many plants - are rather forgiving to their growing conditions. Obviously it is prudent to give them the best start possible but if that has not been case for whatever reason, it it still possible to grow great clematis vines once you understand their specific needs and address them going forward. Unfortunately poor drainage conditions can be extremely harmful and rather pernicious in their effect on plants - if the root system has already been compromised by poor drainage, there's not a lot more you can do, other than to try again!