Not indefinitely, I would still augment with compost or some other organic fertilizer.

It depends on the perennials, and whether the leaves were shredded green (higher nitrogen content) or after they had naturally fallen (lower nutrition content).

Use them, ans if the plants start showing signs of a deficiency, have the soil tested.

Tree leaves have a lot of nutrients that will, eventually, become available to plants, but like anything else that grows they might not have all of, or enough of, the nutrients your plants need.
My planting beds get mulched with shredded leaves each year as well as some of the compost I make using shredded leaves, horse manure, and the kitchen waste we generate and my soil tests tell me that for many years now P, K, Ca, Mg have been staying in the high optimal range with no other nutrient source used. Down in the woodland garden, where tree leaves are allowed to accumulate unshredded native plants, Trillium, Jack in the Pulpit, etc. thrive with nothing else done, and Daffodils apparently like that area as well since they are spreading around with no help from me. Several years ago I planted a dozen Daffs there and this spring I had close to 50 in blossom, in places I did not plant them, too.

Sounds good. Thanks for the info. I do have a good sized compost double bin... but i typically use it for the veggie garden. Maybe i can just spread some around the perennial beds as well to supplement.

Do leaves make good mulch? Just go walk into any forest and find out for yourself! Forests get by just fine using fallen leaves and branches. There is no better system than to use what you have right there. Add a couple of inches each year on top of last year's leaves, and do not turn the soil. The leaves eventually become the soil and the soil will be top quality. After a year, you should no longer need manure, fertilizer, herbicides or any of that chemical nonsense.

Plant Nutrients in Municipal Leaves

I use this document to aid in figuring our nutrient requirements.

Lloyd

Lloyd, i had seen that doc too. They note at the end about there being a slight N fixation using leaves. Would this only be attributed to the leaves being turned into the soil for their farming?

If used as just a mulch, there wouldn't be that issue right?

Correct. On top, as a mulch, there would be negligible N deficiency caused by the leaves. Work it in and there could be issues. Seen N deficiency caused by leaves, wasn't pretty. :-(

Lloyd

Now would leave mold be a fixation issue?

I actually just double dug a few new perennial beds this past weekend and took out some of the subsoil (which is just below the sod in my yard) and then adding/mixed in a ton of crumbly leaf mold.

That, I am not sure of.

I suspect that some of the C has been 'processed' so some of the readily available, easily digested stuff is already consumed ergo it might not be as bad as newly fallen fall leaves. However this is just a WAG on my part.

Lloyd

Sounds good. The beds are settling down from being fluffed up a bit.. so i can mix in some compost and starbucks UCGs to help.

thanks

Some of the nutrients in those leaves would be used by the bacteria as they digested the leaves and some probably would be leached out by snow and rain. Since the remaining nutrients would be more stable they would not show up in nutrient tests. Since the C:N ratio would be closer to 1:1, like finished compost, there should not be any problem with Nitrogen being tied up by the soil bacteria digesting leaf mold, depending on how finished it was, if that leaf mold was tilled into the soil.

I'm having a hell of a time using shredded leaves as mulch, the main culprits are 3 or 4 "Tree of Heaven"s surrounding my property, these things dropped millions of seeds that got mowed up into my shredded leaf pile. After a good rain these things sprout like grass everywhere, easy enough to pull out but quite annoying.

Next year I will try and compost the leaf pile a bit rather than keeping a separate leaf and compost piles, hopefully that will kill off a percentage of the seeds.

I have spoken to my neighbors numerous times, they "like" the trees...

go figure

Tree of Heaven, "Ailanthus altissima" is considered an invasive plant species and it should be eliminated everywhere it grows.

nevermore44, I agree with Lloyd.
I would,if I was you, gather some leaves in a circle of fence wire, so they can finish composting. But I enjoy the composting on most as much as gardening.

I would get a lot of free Starbucks grounds and mix with the leaves in a short time, they will make either a great compost or you can dig them in. They will be ready when they look less like leaves, meaning they are part way broken down. You don't have to wait until they are completely broken down. The coffee grounds will off set any problems with nitrogen deficiency. This should happen quickly. In about a month they should be good to go if the bin is not not too dry or too wet.

The Carbon to Nitrogen ratio of leaves ranges from 40:1 to 80:1 so tree leaves, especially while still fairly fresh, have almost the optimal amount of N we try to build into our compost. One of the reasons that leaves piled up and just moist enough will over the winter produce leaf mold.

Leaves will improve the soil so use them. If the plants seem to lag or slow in growth you can always use the fertilizer of your choice, make it easy. No need to run around with test tubes trying to figure out the soil. Organic matter always helps.

I finally found a lab that would test my soil. But, each sample cost 10 dollars and to find out about organic matter or salt was an five dollars on top of that for each sample. Each sample could cost you 20 dollars and you need about 10? That is 200 dollars.

If that money was put into bagged browns the soil would be a lot better. Using a soil meter or Litmus paper can give you a ph. I have both of those and my soil is about 7. I tried those test tubes you shake up with water and those did not work at all. You just need a basic reading of the ph you can do yourself. You can also research the soil in your area and find out if your soil is acid or alkaline.

Here is a link that might be useful: soil testing lab

Unless you are very obsessive you do not need to have each planting bed tested, sample each bed, mix the soil together, and submit one soil sample to the lab for testing.
A soil pH meter, if it works right, will tell you what your soils pH but it will not tell you if your Calcium and Magnesium are in balance. Since plants need those in balance to properly utilize each that probably is a gardeners need to know item. Litmus papers can give you and indication of your soils pH but again will not tell you anything about the levels of Calcium and Magnesium.
Since a test for the amount of organic matter in soil is quite simple paying a soil testing lab to determine that probably is a waste of your money. These simple soil tests can help a gardener find out more about the soil they have.
1) Structure. From that soil sample put enough of the rest to make a 4 inch level in a clear 1 quart jar, with a tight fitting lid. Fill that jar with water and replace the lid, tightly. Shake the jar vigorously and then let it stand for 24 hours. Your soil will settle out according to soil particle size and weight. A good loam will have about 1-3/4 inch (about 45%) of sand on the bottom. about 1 inch (about 25%) of silt next, about 1 inch (25%) of clay above that, and about 1/4 inch (about 5%) of organic matter on the top.

2) Drainage. Dig a hole 1 foot square and 1 foot deep and fill that with water. After that water drains away refill the hole with more water and time how long it takes that to drain away. Anything less than 2 hours and your soil drains� too quickly and needs more organic matter to slow that drainage down. Anything over 6 hours and the soil drains too slowly and needs lots of organic matter to speed it up.

3) Tilth. Take a handful of your slightly damp soil and squeeze it tightly. When the pressure is released the soil should hold together in that clump, but when poked with a finger that clump should fall apart.

4) Smell. What does your soil smell like? A pleasant, rich earthy odor? Putrid, offensive, repugnant odor? The more organic matter in your soil the more active the soil bacteria will be and the nicer your soil will smell.

5) Life. How many earthworms per shovel full were there? 5 or more indicates a pretty healthy soil. Fewer than 5, according to the Natural Resources Conservation Service, indicates a soil that is not healthy.

That is not too bad, if I just do one sample it is affordable. My soil is fairly uniformly sand all over the garden anyway.