You could dig in compost. A lot of it, maybe a few buckets of sand. It will help break up the clay.
This will break down the compost so the garden is ready for spring if you get the garden ready soon.
Water with it 10 water 1 microbe 0nce a week until the snow flies. Soak it good.Then again as directed in the spring.
Worms.
Grab a couple of big bags of leaves this fall. Add a little water and tuck them away until spring.
In the spring you will have your top dressing / worm food. After everything is in the ground and the plant is growing top dress with this icky 1/2 rotten leaf matter. Add some kitchen scraps once in a while not a lot just enough to feed the worm population. You can put this on in the fall as well. If you are going to add any manure sprinkle it on top of this and water in. Don't dig it in. The little red worms that do all the work are top feeders. and will take care of it for you.
Check this out for the spring time.
Bone Meal. You can also top dress with a 1/2 cup of Garden Gypsum to keep her happy until the bone meal kicks in.
Top dress with a cup of Pure Alfalfa like for rabbits. 1/2 cup once a week once the plant is established. Or better yet 1/8 cup Alfalfa meal
you can get a bag at the local feed store
This is great fertilizer. You can add a little Alaska fish fertilizer to boost it when needed.
As flowering advances back off on the green juice buy 1/2 and feed more bloom booster and Molasses
A little of this will supercharge your microbes and make sure the minerals your plant need are available when needed.
Once a month. every feed during flower.
I found
Grotek 0-50-30 Monster Bloom. As soon as she has stopped stretching late July and is flowering.
Start adding this or something like Alaska 0 10 10 with the Molasses.
