Someone told me oak leaves are too acidic to use for mulch. Is that true?

I believe that they do tend to be acidic, but I'd also think that it depends on what you are wanting to mulch, and what the current levels in your soil are. Oak leaves, and pine straw are used in my area for Azaleas, and Blueberries especially.

Hm... how about rhododendron & strawberries?

holity said:Someone told me oak leaves are too acidic to use for mulch. Is that true?

No its not true. Everything that was alive has a ph, that ph changes as decomposition breaks things down. Completely decayed compost in pretty neutral at the end. No matter what the original ph was at the start.

I would not depend on organic additions to change ph of plantings. It never did for all the pine needles and oak leaves I added to my blueberry.

Only Miracid or sulphur changed my ph.

Azaleas are in the same genus, I believe, as the Rhododendron's, so I think you're good there. I can't say much about Strawberries…The growers here do use a straw mulch, but I doubt that it is pine straw. Maybe someone with more knowledge of Strawberries may jump in.

Tom, I've heard that before too!

Maybe I'll just put these oak leaves in the leaf mould pile.

The first leaves to fall were 90% maple; I shredded them with the mower and emptied the bag out over all my garden beds.

Now the leaves on my lawn are 90% oak.

Maybe the best thing is to compost them!!!

I've used oak leaves for years as mulch on everything. I prefer them to be aged and/or shredded simply because they all end up on my patio otherwise.

I was wondering if shredded maple leaves matt and if I could go ahead and add them to the oak leaves I am shredding.

Smiles,
Lyn

Lyn, I put shredded maple leaves down for mulch last fall too, and they worked just fine.
-Terri

I much my gardens with oak leaves each Fall and having been doing so for years and years. There is never any problem.

I too have used oak leaves for decades. I have used these leaves over canna and ginger rhizomes around all types of landscape evergreens and over asparagus (dormant now) and garlic. It goes over my garlic ONLY if the temperatures get down to the mid-teens or lower. I put 4-6" of oak leaves over/around these plants/rhizomes. However I don't shred them with my mower if I am using them only as a winter-protector mulch. I do shred them with my mower when I put them in the compost pile though.

Terri......

Thanks for the information. I live in a small gold mining town in the mountains of northern California and they don't sell mulch up here, so I have to go out and gather it and bring it back to the garden.

I've always shredded the fresh oak leaves with my weed whacker in a garbage can. (I don't have much lawn and don't own a lawn mower ) I do have a maple tree, but I've always just bagged the leaves and allowed them to decompose over the winter and used them in the spring because, unshredded, they matt and inhibit water and air to get down to the soil. Now, I'll just added them to the garbage can and use them.

Smiles,
Lyn

I've always shredded the fresh oak leaves with my weed whacker in a garbage can.


^^^^ Ingenious, RoseBlush! You sort of have a garden food processor there.

I used all my leaves including the leaves of giant oak trees, in my garden and lawn. My lawn mower fine-mulches them for a nice layer on the lawn to over-winter. And the rest (I have TONS of leaves) is a base-filler for bark mulch in the spring. I have to buy less bark mulch this way. All the plants seem to love it. Every once in awhile I toss it in to the forest bed to cover low spots.

Since I can't buy bark mulch up here, I only mulch with leaves. Sometimes, I can get rotten hay to put down before I put down my top layer of leaves to help feed the soil.

Basically, since I only have two trees on my property, I go to a friend's place to gather leaves for mulch.

Thanks again for the information. Now, I won't have bags of leaves along the side of the house and can use the leaves as soon as I rake them up.

Smiles,
Lyn

From things people have said, the extra step my friend always takes may be unnecessary.

He thought that oak leaves had "too much tannin" to break down during the first year. So he would bag all his oak leaves DRY and let them "age" for a year.

Then he would turn them into his garden WHOLE, late the next fall. He felt they were broken down "enough" to plant next spring. (I could see whole leaves half-buried in his seed bed and I thought that was "wrong".)

I thought that, if he was going to save them for a year anyway, why not let them compost during that time? And I think he "should" have chopped them before turning them under. But his method worked for him: his garden soil did improve each year.

Possibly the bags kept them from blowing away, and I know that he just "didn't like" the idea of composting. he had once managed to collect so much soggy green stuff that he made a layer of slime on top of some plywood, and ever after thought composting was vile.

Everyone has their own preferred methods, and it takes all kinds! But apparently, almost any method can be made to work.

@RickCorey

If I go out to collect my oak leaves from BJ's place before this year's leaves have dropped, I am collecting aged oak leaves. After the leaves have fallen, BJ rakes the areas where they are active around her house and hauls them to a part of her property that is kind of out of the way, but near the road she uses for her quad.

In our climate, the leaves sit there through our colder winter with 25 to 50 inches of rain and periodic snow and through the high temps of our summer. By the time I go to collect the leaves, they have broken down to the point where I do not need to shred them.

The fresh oak leaves are from my neighbor's trees which blow into my yard. The neighbor above me has been removing his junk pine trees and leaving the oaks to make his place more fire safe. The neighbor next door removed four pines, too, and now leaves from both of their properties are landing in my garden.

In years past, I've never had an issue in the garden when I did use fresh oak leaves, but they were shredded when I put them down, so they broke down faster than unshredded leaves would ... if they stayed put.

I have a no-till garden, so I've never dug the leaves into the gardening beds. I don't know if that would make a difference.

Smiles,
Lyn

>> In our climate, the leaves sit there through our colder winter with 25 to 50 inches of rain and periodic snow and through the high temps of our summer.

That's what I would do: pile them exposed to rain and worms, and let them compost as much as they are willing to.

>> In years past, I've never had an issue in the garden when I did use fresh oak leaves, but they were shredded when I put them down,

>> I have a no-till garden,

My guess is that that adds a few months to the time it takes for them to reach the deeper soil. If there is any reason to fear tannin in oak leaves (and I have no reason to think there is), that extra time may be protecting you.

But maybe the only "danger" is that the tanin makes them break down slower than they otherwise would. If so, composting or aging them for 8-10 months still seems sufficient.

My own stubborn, unfounded prejudice is that things "should" be composted before being turned under. In a no-till garden, you're mulching with them, so my prejudice doesn't even apply.

i like the fact that everyone has "their own way", and they all work.

>>>>i like the fact that everyone has "their own way", and they all work.

Me, too. However, I think what we do in our gardens is often dictated by our climate and soil .... and, of course, what we choose to grow.

Smiles,
Lyn

I love leaves, and I use all kinds, including a lot of pin oak from my neighbor.

The only problem I've seen in mulching with them is that a too-thick layer can clump together to form a mat that isn't penetrable to water. Even through a wet and snowy winter that area of soil stayed dry.

Karen

The leaves of the pin oak are a bit smaller than those of the white and red oak, the varieties I have. Thus the pin oak leaves would compact more readily. Even with a 4-6" layer of leaves, I have never seen my leaves mat enough to shed water. Of course, I only use them through the winter, and ultimately will chop them with my mulching mower and then put them in my compost pile to break down.