Yes, you've got the right idea. I recommend mowing the leaves and then using them as a mulch on top of the garden soil. Don't try to mix them with the soil, allow them to decompose on top of the soil. If the leaves are shredded/mowed, four inches would be ideal. You live in an area that gets plenty of rain so the leaves should be pretty well along the road to humus by the time spring arrives.

Plant your plants in the soil under this 'mulch' and keep the mulch away from the plant stems until the plants are established. Next year, repeat the process but don't disturb the previous layer of mulch, just layer it on top.

Soil naturally forms layers. The very top layer is where the action is at. The goal is to create the O1 and O2 horizons and they will feed the A horizon. If the soil is tilled, the process needs to be restarted with a O2 on top of an O1.

My new love is shredded leaves. :)

Here is a link that might be useful: Soil horizons

Shredded leaves added to your soil is a great way to add organic matter. Add them as soon as your beds are empty and you can get a hold of them to start shredding. I spread them about 2-3" deep and turn them under the depth of a garden fork. Then i do it again; another layer, turn them into the soil, water a little and let the dirt do it's work. The microbes actually will work all winter breaking them down, albeit pretty slow, but by spring planting they'll be incorporated. Not sure if Long Island gets a very cold or long winter but putting the garden to bed with a blanket of shredded leaves would be a bonus. Dig them in as soon as ground can worked in spring.

Organic matter is vegetative material. Leaves are vegetative material. Leaves then are organic matter and can be added to soil with much better results then peat moss would since those leaves still have nutrients.
I have used shredded leaves as mulch on my planting beds, leaving them in place through the growing season to aid in weed suppression, moisture retention, soil temperature control, and to add organic matter to the soil.
There is no need to till those leaves into the soil since over time the soil bacteria will do that for you.
I have also composted shredded leaves and have mulch mowed leaves into the soil I have and have watched what started out as a 6 inch thick layer of leaves, mulched down to about an inch, be digested by the Soil Food Web before snow covered the ground.
Leaves, being free, are the best source of organic matter you can add to your soil.

I use leave in soil, as mulch & in my compost pile every year.

Agreed, it's a good thing. And making lemonade out of other people's (free) lemons is just fun! When I used to live in an area where people bagged leaves, I would put up to 18" (usually unshredded) and they would be gone by spring. The oak leaves I have here take a bit longer but I've noticed after a few years of putting them down (on beds that were grass until very recently) they are starting to disappear quicker, like whatever microbes or worms or whatever eats them has multiplied to handle the load. Luckily this yard is full of huge deciduous trees because nobody bags any yard waste here.

For some reason my yard collects metal wash tubs. Two here when I moved in and I snagged another one from the abandoned yard next door last fall, too late to bother planting it. So we filled it with leaves that were shredded and mixed with grass from the mower to decompose over winter. This spring I didn't need to add anything to it, just filled it with Coleus, Perilla, and Persian shield cuttings which are doing spectacularly.

Agreed with not tilling them. Mother nature puts leaves on top of the soil, not under the surface. Over time, the decomposed materials will be at the appropriate levels without any mechanical intervention on your part. Nobody tills the forest floor. I think you are past this point, marcantonio, but for whoever might read, tilling can be helpful the first time a new area is gardened, reclaimed from grass or weeds, that is hard to dig in. After that, not necessary if you are putting plenty of organic material on top at least yearly.

I have a nice big avocado tree in my neighbors backyard that leaves a ton of leaves every year. My Grandfather would always rake them up and throw them out. I would always ask him "Why are you raking them up? They will eventually disappear." Well now they stay on the ground and mulch in.

Someone told me that Avocado trees begin to decline if you clean up its leaves. It is recommended to leave the leaves where they fall.

Leaving stuff on the ground the way Nature does? That's crazy talk! :-p

Now where's my copy of "God, St. Francis and the Lawn"...

GOD AND ST. FRANCIS DISCUSSING LAWNS
GOD: Francis, you know all about gardens and nature. What in the world is going on down there? What happened to the dandelions, violets, thistle and stuff I started eons ago? I had a perfect, no-maintenance garden plan. Those plants grow in any type of soil, withstand drought and multiply with abandon. The nectar from the long lasting blossoms attracts butterflies, honey bees and flocks of songbirds. I expected to see a vast garden of colors by now. But all I see are these green rectangles.

ST. FRANCIS: It's the tribes that settled there, Lord. The Suburbanites. They started calling your flowers "weeds" and went to great lengths to kill them and replace them with grass.

GOD: Grass? But it's so boring. It's not colorful. It doesn't attract butterflies, birds and bees, only grubs and sod worms. It's temperamental with temperatures. Do these Suburbanites really want all that grass growing there?

ST. FRANCIS: Apparently so, Lord. They go to great pains to grow it and keep it green. They begin each spring by fertilizing grass and poisoning any other plant that crops up in the lawn.

GOD: The spring rains and warm weather probably make grass grow really fast. That must make the Suburbanites happy.

ST. FRANCIS: Apparently not, Lord. As soon as it grows a little, they cut it-sometimes twice a week.

GOD: They cut it? Do they then bale it like hay?

ST. FRANCIS: Not exactly, Lord. Most of them rake it up and put it in bags.

GOD: They bag it? Why? Is it a cash crop? Do they sell it?

ST. FRANCIS: No Sir. Just the opposite. They pay to throw it away.

GOD: Now let me get this straight. They fertilize grass so it will grow. And when it does grow, they cut it off and pay to throw it away?

ST. FRANCIS: Yes, Sir.

GOD: These Suburbanites must be relieved in the summer when we cut back on the rain and turn up the heat. That surely slows the growth and saves them a lot of work.

ST. FRANCIS: You aren't going to believe this Lord. When the grass stops growing so fast, they drag out hoses and pay more money to water it so they can continue to mow it and pay to get rid of it.

GOD: What nonsense. At least they kept some of the trees. That was a sheer stroke of genius, if I do say so myself. The trees grow leaves in the spring to provide beauty and shade in the summer. In the autumn they fall to the ground and form a natural blanket to keep moisture in the soil and protect the trees and bushes. Plus, as they rot, the leaves form compost to enhance the soil. It's a natural circle of life.

ST. FRANCIS: You better sit down, Lord. The Suburbanites have drawn a new circle. As soon as the leaves fall, they rake them into great piles and pay to have them hauled away.

GOD: No. What do they do to protect the shrub and tree roots in the winter and to keep the soil moist and loose?

ST. FRANCIS: After throwing away the leaves, they go out and buy something which they call mulch. They haul it home and spread it around in place of the leaves.

GOD: And where do they get this mulch?

ST. FRANCIS: They cut down trees and grind them up to make the mulch.

GOD: Enough. I don't want to think about this anymore. St. Catherine, you're in charge of the arts. What movie have they scheduled for us tonight?"

ST. CATHERINE: "Dumb and Dumber", Lord. It's a really stupid movie about.....

GOD: Never mind, I think I just heard the whole story from St. Francis.

Good for adding food for worms and soil microbes. However, leaves aren't very nutrient rich compared to other composts like dairy manure (much better than feedyard manure - because of animal diet differences).

I would recommend adding leaves, untreated wood mulch, and also dairy manure (if available). The combination of these three will provide the balance of increasing porosity, carbon, and nutrients.

You dont say?? Too bad dairy manure doesnt fall from trees...Lol As Ive recently switched from steer to good ol milk cow and it is quite a bit more expensive but minus all the salts. I have better results with steer manure and for 1/5 of the price I dont really notice any salt damage. Im currently looking for a good source of rabbit poop. I found a good source of 50 pound bags of compost with %10 worm casting for $8 a bag from a good worm farm in San Diego that would go well with some other type of poop:-)Plus I have so many bags of steer and chicken sheeit laying around.

That St Francis and God thing was so on point. I agree with the reasoning wholeheartedly! I cannot believe how much I despise my HUGE front yard and the time and effort that goes into keeping it green and "square". I cannot understand the reasoning of man. Ticky Tacky

One study I saw many years ago indicated tree leaves may have about the same nutrient levels as cattle manure but there do not appear to be many studies that give actual numbers. I did find one some time back that lists
N = 0.4 to 0.8 percent
P = 0.15 to 0.3 percent
K = 0.3 to 0.6 percent and
Ca = 1.5 to 3.0 percent.
Leaves can make fairly significant nutrient contributions to your soil, although composting them with animal manures would make for something better.
Anyone that lives where there are deciduous trees and does not use those that fall on their property is throwing away a lot of money every year.

Great story kimmsr! "God" must approve of my former lawn. Since I went organic it's become a mix of dandelions, clover, yarrow, and some grasses. Living on a large acreage it's impossible to keep the weeds out without using more noxious chemicals than I'm willing to.

I only have a few deciduous trees (aspen) within my fenced house yard but every fall I rake the leaves off the 'lawn' onto the area under the trees. Strange, but by the next summer they are gone, and they didn't blow away.

While the nutrient level numbers may be interesting I think there is more to organic amendments than N/P/K as there are a lot of minerals in leaves and other organics which may have more value than we think. It's one of the reasons I like alfalfa pellets as an amendment. Alfalfa being a very deep rooted plant brings up minerals that other plants cannot access.

Keep in mind that the nutrients listed are what is readily available, pretty soluble, and is not necessarily a reflection of what is all there. Since the primary source of nutrients I used for many years was compost, made of shredded leaves, kitchen waste, animal manures, and yard waste, and shredded leaves as mulch and since the soil pH here went from 5.7 to 7.2 and P and K and Ca and Mg went from low to high optimal there must be something there that does not show in any nutrient test.

A few year back, I read that man may eat oak leave because they are high in nutrients & protein. I think they where speaking of a colds cereal of some kind. May have been the same guy who said we should farm whales for their milk, it is 100 times richer(?) then cows milk. The whale will not cause the Rain Forest to burn or "Gases" to the ozone, IMO.