I'm a bit confused. Your kitchen scraps will be mostly nitrogenous. Cut down perennials will be more 'green' ie nitrogenous than Autumn leaves since they are generally cut down before they are completely dry and dead. The leaves are a 'brown' ie more carbon. So adding shredded Autumn leaves doesn't add nitrogen.... unless they are still green when shredded.

Personally, I put it all on the compost heap and then spread that on the soil, rather than digging stuff in 'raw'.

Hi floral uk
Yeah, I've found that I am sometimes a very confusing gardener !!
As you stated, the perennials are a "green" (high nitrogen) while the dead (brown) leaves are high in carbon. And I've read in some posts that, when adding nitrogen sources to your compost pile, you need to add a much larger portion of carbon. This is what I invariably do in the summer: combine freshly cut grass with a significantly larger amount of leaves that I collected and shredded the previous fall. As usual, I'll rake the dead leaves in a few months, shred them and store in bags, ready for next year's compost pile.

My main concern is how best to use the perennials growing now. In readying my garden for the cold months ahead, I typically cut down all my perennials (and what few annuals I have) just a bit above soil level. Rather than pitching them onto the compost pile (particularly since I have no browns to mix with them), can I chop up these flowers into small pieces and dig them into the soil, just as I do with scraps from the kitchen, in order to feed the worms and other creatures and improve the soil?

I'm thinking that these perennials might not decompose as quickly as the kitchen scraps.
Bottom line is I'm just trying to get the most benefit from all these flowers I'll be cutting down.

Thanks so much for your interest and response!

I would leave them in the beds. Do you mulch during the winter? I shred fall leaves with the mower and mulch over the clipped perennials. I usually don't bury them in the soil since they aren't going to smell like decomposing veggie scraps, so I just cut them and leave them on top of last season's mulch, then cover with a fresh layer.

It's really your call on what you want to do with them, either way works.

Numerous studies of nutrients of fallen tree leaves indicate they contain (depending on age) about 20 pounds of
nitrogen per ton of leaves, and have a Carbon to Nitrogen ratio of about 40 to 1. Freshly fallen tree leaves will compost quite well by themselves when piled up, if adequate amounts of water are added.
The trimmings from perennials will have nutrients those plants removed from the soil they grew in and those nutrients could be recovered by either composting them or putting them back into the soil they grew in. There is no need to add "lots of Nitrogen" when that is done as long as the soil is a fairly good and healthy with an active Soil Food Web.