The old horticultural myth is that pine needles are acidifying and so are often recommended for blueberries. Pine needles actually have very little ability to lower pH but do make a fine mulch, although needles aren't as nutritious as leaves- but leaves need to be shredded or blow away and they break down faster.

The act of smothering the grass under at least a part of the drip line will invigorate your peaches but you will almost certainly need to apply some spray and prune properly to get those trees into production. If you want my minimal spray program, e-mail me.

I mulch all of my peach trees in pine straw, so if you have it, use it. As it breaks down, it will enrich the soil, keep out weeds, and retain moisture. From your picture, the trees need to be pruned to an open vase system, which should be done right before bud break. Feed them some 10-10-10 after bud break. Be sure to vigorously thin them at about marble size. Then add some calcium nitrate at about golf ball size. This will help them to size up. You'll to need to spray for insects right after fruit set, and watch out for borers. The Clemson University website has loads of information to help you, as will all of us here.

The reason I offered you my spray program is that my hunch is your pest pressure is similar to mine as I'm in SE NY. I also think Rutgers might be more familiar with your conditions than Clemson although no university source info is completely reliable regarding home orchards. Their true expertise is in commercial production. Their information is rarely up to date on pest control products for home owners.

Either University can provide guidance on pruning and Rayrose is right that they are most often pruned to an open center. In Jersey the commercial guys often prune after bud break to reduce canker threat while further south apparently they prune earlier for different issues.

Here's what Penn State says about pruning peaches in Pennsylvania.

"Always prune most stone fruit trees in late winter. The best time to prune is from just before bloom to 2 weeks after petal fall. Do not prune the trees from January through March, and do not prune before budswell. Stone fruit trees are very susceptible to a disease called cytospora canker. If pruned in the winter, the trees cannot protect the pruning wounds from infection by this disease."

Funny how the first sentence is contradicted by the rest of it. It should have said early spring instead of late winter. If this advice was for commercial growers I bet it would have been edited better.

Here's a link to the entire article. It will lead you to much of the other pruning info you need as well.

Here is a link that might be useful: when to prune

I use pine needles around my blueberries, but I agree with Hman, that they won't acidify the soil. I like them because they control weeds, allow moisture penetration better than most mulches, and last a relatively long time. I would sure think they would work for peach trees as well.

I have a free supply of pine needles and started using them for my strawberries. Keeps the fruits off the ground. Also good covering mulch for the winter, Then started using them for potted plants, as you don't have much room for mulch in pots. I just covered my perennials with the mulch this fall. I like them with my raspberries too. I cover around raspberries with compost in the spring, and since they are rather low in nitrogen, one can bury the old mulch with compost, and just add fresh, Removing mulch to add compost is a pain!
I burn wood at my cottage and noticed the bark of oaks, ash and maples would often breakdown to finished compost quickly. Like some one threw dirt all over my wood! So I use bark on most plants up north. The oak and maple bark help a lot to supply compost to my bamboo, currants, and gooseberries up north. It's nice to have free products! The soil there is super rich anyway, black as oil, A few hundred years of old growth forest will do that to a soil.
Anyway I find pine needles and tree bark really good mulches. Not to mention the price is right. I could probably harvest pine bark too, but too much work! The oak, ash and maple are easy since I'm splitting the wood to burn anyway.

The old horticultural myth is that pine needles are acidifying and so are often recommended for blueberries""

THen why are most forests that are acidic pine forests?

CP, because pine trees do well in acidic soils- or at least conditions that create acidic soil. Ample precip being top on the list, I guess.

How would the specific chemicals in pine needles be particularly acidifying? They do contain less calcium, in general, then the leaves of deciduous trees, but they contain less of most nutrients. They are lighter feeders. They pick up and return nutrients the same way deciduous trees do and I don't see the mechanism by which they could acidify by their presence.

If you are curious, do your own experiment. I've already done so but don't expect others to base their opinions on that. I tested soil under a white pine grove where needles had been allowed to compost for about 80 years and compared it to nearby soil that was pasture where the needles didn't reach- same pH- several tests.

I noticed that the NY Botanical Garden was using pine straw in their demonstration vegetable garden and was told that its affect was neutral by an employee there. They are frequently asked about it, I was told.

If you search for it, you can probably come up with a more researched evaluation. I will be happy to be contradicted because that's the main way I learn anything. One benefit of being excessively assertive.

Here, I found a better source than me for you.

Here is a link that might be useful: pine needle myth

I'm one of those doubting Thomases, and I don't believe everything I read, especially from extension offices. I've read a number of things on the Clemson extension services website that aren't fact, but just the opinion of the author, who in many cases, has only a master gardeners certificate. I've done my own study about adding pine straw to my blueberry bushes, and I've found that it does lower the ph. I planted my BB 5 years ago and recorded the soil ph before application of pine needle mulch, and three years later found the ph to be lower by a factor of .4. This was also considering that the ph of my city water, with which I watered the bushes was 8.3. So I'm a firm believer that pine straw mulch does lower soil ph over a period of time.

The claim seems to be based on careful research by Dr. Abigail Maynard of the U. of Conn, not a master gardener. She apparently applied huge amounts of pine straw over a soil bed for several seasons, as well as other organic materials on other beds, and found no significant change in pH of underlying soil with any of the organic materials she used.

I couldn't find the actual research paper, however- just a lot of different sources that referenced it.

I suppose it's possible that not all pine straw is equal, but as I said, nothing she tried was affective. Probably means sawdust doesn't work either.

Ray if true you will have to eventually use something else as PH drops so low as to even kill blueberries.
The truth lies somewhere between. Green pine needles are acidic, but rarely are used. With break down acidity is lost. Much like vinegar. the only thing that seems to hold acidity is sulfur. And eventually even sulfur breaks down after a few years.Probably because it is leeched elsewhere.
Rainwater is acidic yet basic soils still exist. I'm pretty sure it rains everywhere. So bottom line is the acidity is not a problem if using as mulch.
If you Google the subject nobody anymore says pine straw remains acidic.

This post was edited by Drew51 on Wed, Oct 9, 13 at 19:17

Drew the city water that I use keeps up the ph, so I don't have to add anything.

Thank you all for the replies.
So my plan this winter from what you've all said to me is:
- Lay down the pine needles as mulch. I plan on a large rectangle to cover all 5-6 peach trees and the space in between.
- Prune the trees into an open vase system
- Feed them 10-10-10 after bud break

I do have some questions though. I'm not quite sure what rayrose means by "Be sure to vigorously thin them at about marble size. Then add some calcium nitrate at about golf ball size."

As for the "Open Vase System" is this what you mean:
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Also, when I moved here this is one of the peach trees I found. Any chance on saving it?
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And lastly, here are some more pictures of my peach trees:
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Thank you all for the help so far

Ray, OK, but you do realize you are a minority opinion that most think what you say is myth? It's hard to believe what you say as everybody else says it ain't so. I could not find even one reference in support. But you know I have been there too, so more power to you! If it works, don't fix it!
Even so with what you reported, i stick by what i said. You reported a drop in PH even with city water. So the PH could keep dropping.

The main stream is often incorrect. And as HM says some species might be different, not all pines are equal. I myself use pine bark around my blueberries, but I also use sulfur and ammonium sulfate a few times a year. it works for me . My blueberries look great! When PH is correct they grow like weeds. Mine put on about 2 feet of growth this year. Nice strong, thick growth. I also water mostly with rain water.Occasionally I like to use the hose to really soak the bed. I just don't have enough rain water to always do this.
I figure the PH is so low, it probably helps. I keep the PH at around 5.0. I have to be careful not to let it drop too far down. Hard to figure out how much sulfur to use. It takes so long to work, easy to overdose it, and not know for months. I think I have it where I want it, and it should be good for a couple years before I need to add more sulfur.

This post was edited by Drew51 on Thu, Oct 10, 13 at 13:15

Dont think of what i said as a challenge, it was a legit question :) I only speak of what I know, and if im wrong too, well, I learn more.

I was more suggesting a very long term acidification. You make a good point though. So are pines there because of pre exsisting acidic soil, or is the soil aciding because of the pine? I would assume that would be relative to the site. I do know all the peat bogs here are highly acidic, and those mostly contain ceders pine and tamarak.

At the very least, it is slow to beak down, which that alone makes it a good mulch. Most barley last a season in my experience. Even if pine needles eventually acidify the soil, I dont think the effects would be fast enough to really effect the trees.

I appreciate the link too.

CT, Tone is difficult to convey over the internet, but there was nothing offensive in your words. I took it as a kind of challenge to get my brain going and rectify the concept of conifers thriving in acidic soils but them not making it that way.

Also, Ray, I don't presume to know enough or have any solid evidence that your individual study was the victim of inaccurate measurements or some other mistake on your end. Hort research has so many variables that nothing is ever in stone but as long as the verifiable research follows my experience I will run with it, of course.

I have often read of research that blueberries cannot function productively out of a very narrow range of acidic soil but I've seen several instances of productive blueberries growing in mulched soils close to a mid 6 pH. This is just one example of where I've found the established, researched position to be contradicted by my reality, so I also sympathize.

Kelby, it is not always advisable to use a 10-10-10 formula to fertilize trees. Sometimes soils already contain excessive phosphorus and too much of it can create an imbalance in the soil. Why not contact your local cooperative extension and arrange go test your soil and get a more specific nutrient recipe for your individual soil? The tests are not expensive.

A deficiency of P is not a common experience and I usually don't include it in my applications.

Kelby,

Your diagram of the open vase sysytem is accurate. You may want to get your soil tested, as was suggested. Then you'll know exactly what to feed the trees. Your trees will overpollinate the blooms, meaning you'll have lots of peaches, but the tree cannot support that many peaches, so it will naturally abort a number of the fruits.
But you also need to eliminate many of the peaches that are not naturally aborted, or else all you wiil get are a lot of very small peaches. That's what I mean by vigorously thin the fruit. In my area most of the commercial peach growers add calcium nitrate (15.5- 0-0) after they have thinned their trees and the fruit reaches golf ball size. They do this to make the peaches get larger. You can do this or not, I do, and I get larger peaches.
I would take out the small tree in your photo. You'd be better off planting a new tree. The other trees look great and you should get a nice harvest next year. Someone has given you a very nice prize.

So I added the pine needles around the peach trees. Wanted to show you how it looks and maybe get some feedback.

{{gwi:125286}}

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Kelby,
If they were mine,I'd pull the mulch a few inches away from the trunks,but they look good though.
The right amount of mulch is about 2-4 inches thick and should extend out to the drip line. Brady

Kelby,

It looks realy good, but as Brady said, pull the mulch away from the trunks. It will help you to look out for borers. They like to enter trees close to the soil line.
The next thing on your agenda will be the winter prune to an open vase system. I do this in late January, but in your area, it might be a little later, but do it before bud swell.

Hi all, I have tons of pine needles from two Norway pines that are over twenty feet tall. Can I use the brown needles around all of the trees in my orchard? It would be easier to mow around the trees than by using my existing black pine bark mulch. Will the mulch influence the taste of next years apples, apricots, cherries, peaches, pears, currants, and plums? Many thanks, Mrs. G

I don't see how it could influence taste? Pine is pine, needles, bark, all the same thing. I would use it.

edit: well, it looks like that PDF access does not work, so here is the ref:
"Impact of Mulches on Landscape Plants and the Environment --- A Review" - by Linda Chalker-Scott J. Environ. Hort. 25(4):239-249. December 2007

Mulch Problems --- Real and Perceived

Acidification. Organic mulches such as wood chips and bark are thought by some to be soil acidifiers. No scientific research supports this, and in fact studies refute this perception. One study found neither pine bark nor pine needles had any affect on soil pH (51). A second report (60) found bare soil to be more acidic than soil covered by inorganic mulch, and that shredded bark and wood chips were least acidifying of all treatments. Similarly, a year-long study found that the soils under organic mulches were either more alkaline or not affected by mulch treatment (100).

ItâÂÂs likely that in artificial conditions, such as nursery production, that woody materials do have an acidifying effect when they are used as part of a potting medium. Release of phenolic acids is one stage of the decomposition of woody material, and if this material comprises the bulk of medium then acidification is likely to occur. In a field situation, however, where the woody material is used as a mulch (and not worked into the soil), any acidification will be localized within the mulch layer and have little effect on the vast underlying soil environment below. Thus, soil acidification due to mulching with woody plant material is unlikely to occur under real world conditions.

51. Greenly, K. and D. Rakow. 1995. The effects of mulch type and depth on weed and tree growth. J. Arboriculture 21:225-232.

52. Iles, J.K. and M.S. Dosmann. 1999. Effect of organic and mineral mulches on soil properties and growth of âÂÂFairview Flame Râ red maple trees. J. Arboriculture 25:163-167.

53. Pickering, J.S. and A. Shepherd. 2000. Evaluation of organic landscape mulches: composition and nutrient release characteristics. Arboricultural J. 23:175-187.

Here is a link that might be useful: Impact of Mulches on Landscape Plants and the Environment

This post was edited by Fascist_Nation on Tue, Oct 22, 13 at 10:45

"....but as Brady said, pull the mulch away from the trunks. It will help you to look out for borers. They like to enter trees close to the soil line. ..."

Yes, because you wouldn't want anything getting in the way of their access to your soil line. . . . sorry couldn't help myself.

Regardless, as was said (in a non-arid environment) you should pull mulch 2"-12" away from the trunk to prevent moisture accumulating causing rot and overwintering rodents in the mulch snacking on your trunk when they get desperate. Mulch up against the tree can also protect trunk snacking insects at other times of the year especially on young trees. I'd shoot more for 12" than 2" as the mulch has a way of migrating into the open area near the trunk, so there is less maintenance to keep it away with this beginning distance and the area dries out quicker.

Supposedly there is an Australian study that demonstrated more than 4" thick organic mulch prevented rain (water) from passing through. I have never found that study. But it is not unreasonable as organic mulch will dry out and behave as a sponge...so a good deal of initial water landing upon the surface may get absorbed/adsorbed before the mulch saturates and water makes it through.

In my experience, organic mulch shrinks within 2-3 weeks by half once applied: presumably due to settling and water loss. So I apply twice as thick as my target height.