Bark mulch

North Chelmsford, MA(Zone 6b)

My townhouse community is barkmulched each spring. The landscaper likes to do it, the governing board likes its appearance, but...we've been here twenty-odd years and I'm not sure the soil likes it. When we dig down to plant new perennials we find layers of old bark mulch. ( In places where the plows put snow we get alternating bands of sand and bark mulch.)
There is not a hope in the world of changing this spring routine; so my question is: What can we do to ameliorate the situation? Nitrogen? Lime? Our soil here is not fertile and is a mix of silt, clay tree roots and occasionally sand. It is acid, as is usual around this part of New England. I should think the soil would benefit from the lime anyway.

Ayrshire Scotland, United Kingdom

HI Quiltjean, it really depends on the type of plants you want to grow as adding lime will harm some plants while others will love it, you mentioned all the soil in your area is acidic, so I can only asume that all the trees/shrubs and flowers in your area thrive in this, there is more chance of growing more plants in different soils IF say you used the raised bed style of growing, then adding good new soil that is not acidic at all, but to be honest, you will find it very difficult to change your PH by just adding lime as the plants will soon bed there roots into the original acidic soil deeper down, by adding a mulch every year the soil should be nice and loamy for acid loving plants and maybe it just needs dug in more before the new stuff arrives on top of the old. hope someone else can come in and give you some more ideas as I have never heard lime alone helping acidic soil on it's own. good luck. WeeNel.

La Vergne, TN

WeeNel is correct, you never add Lime/Sulfur unless you get a soil test to confirm you need it. Lime will lower the Ph not help make your soil better. Wee said it, turn the mulch in as far as you can in the late late fall/winter so it will be ready to go in the spring. Time will take care of the rest. Also, try doing what My kids and I do. After it rains go on a worm relocation program. Find worms and put them where you want them. A lot will stay and help decompose the mulch. You could always tell the board to not mulch your area and do it yourself with some nice shredded pine. It decomposes fast.

North Chelmsford, MA(Zone 6b)

You and WeeNel are right. I'm sorry if I gave the impression that we wanted to change the pH of several acres of land; what I'm interested in is finding a means to get the bark mulch layers in selected spaces to break down. Our soil is so acid, the mulch so sour, that nothing grows very well in established beds. Condominium rules are strict, so we can neither turn over too much soil, ask the Board to omit mulching, nor mulch with pine needles.
What I asked about was some means of breaking down the bark mulch. Now that I know lime won't work, what about nitrogen fertilizer?
Wish we had worms, but the soil is horrible and we rarely find them.

La Vergne, TN

well, I would try to turn even a little. Nitrogen is taken up from the plants so putting it on a non-living material doesn't do anything for the mulch, it might help with some fungus that might be there trying to breakdown the mulch for food. do you see any mushrooms or slime, thats a sign that the y are breaking down the mulch.

Ayrshire Scotland, United Kingdom

Sorry Quiltjean, I have to agree with Kitten when she said IF your whole area is all acidic soil, there is no way you will be able to change what nature has done as regards the acidity of the surrounding landscape which is acid soil, but you can improve what soil or rather the quality of it by adding loads of good quality peat to the soil you have, this dig into the horrible soil condition will allow air into it, this in turn will help worms etc to be able to breath, feed off the decaying bark mulch and let more air down into the roots of plants you may wish to add to the beds or borders, there is also feeds available to add to acidic soils which will help any plants.
There is a vast range of plants that love your soil from trees, shrubs and flowering plants and as I have this type of soil here on the West Coast of Scotland, you have the enjoyment of growing things that others cant, most of them withstand cold winters, are evergreen and will be flowering or giving lovely foliage colours all year round if you choose things that have different seasonal advantages.
things like Magnolias, Rhododendrons, Azaleas, Heathers, Ferns, Camellias, Philesia,
some Holly's and many more. these are all easy to care for and require nothing more than good care to get them started and a feed every other year, but will give you lots of colour and enjoyment all year round, some Acers with different foliage colours are really lovely come Autumn when the leaves change colours from Bronze, yellow to bright red/orange, they are not all huge trees so if you select well, you will soon start to see the area completely transformed. hope this helps you out a bit and if we still have not understood the problems you have, please just get back to us, you seem to be so keen to change your outlook and garden area, it would be a shame if we were still missing the points. Good luck. WeeNel.

Sacramento, CA(Zone 9a)

Maybe someone can enlighten me, but I was always told that woody mulch like this actually takes nitrogen out of the soil underneath it as it is the nitrogen that works to decompose the mulch. If that's the case, wouldn't several layers of bark mulch imply that quiltjean would have a nitrogen deficiency in her soil?

Dublin, CA(Zone 9a)

I don't think mulch will deplete enough nitrogen to cause problems. And especially if the beds are fertilized that would more than make up for any that was lost.

Long Beach, CA(Zone 10a)

From reading the initial post and those that responded, I think the issue here is twofold:

1.) Is the "bark mulch" that is being put down, the type that is shredded or in little chunks?

2.) Is this "bark mulch" being cultivated into the soil each spring when the soil thaws out, or just used as a top dressing?

IF this mulch is the shredded type of mulch, it will break down faster than the chunky stuff. (The definition of "mulch" can be different things to different people. Many people use those bags of chunky bark as a "mulch" ...which it technically isn't...then they cultivate it into the soil and it takes forever to break down and causes nitrogen deficiency in your soil as the available nitrogen is used up in the decomposition process, thus robbing your plants of nitrgogen until it's all decomposed)

It would seem to me that annual applications of this "bark mulch" is just exacebating the problem as it never gets a chance to fully decompose with each successive "layer".and continues to keep your soil acidic...which isn't necessarily a bad thing.

A more detailed description of the mulch they are putting down, and how much they apply would make it easier to find a solution to the problem.

North Chelmsford, MA(Zone 6b)

Jasperdale--BINGO! It's shredded. I'm not even sure it's not dyed shredded wood! Anyway, it's applied every year, hence the layers, and hence the query about lime or hi-N fertilizer. I think you must be clairvoyant.
The nice workers--not landscapers--come around each year and rake off the leaves but do not turn the shred. (They would charge extra for digging.) I know this only because this spring I came across a hosta that had come out and been replaced--upside down.
Thank you for your reply!

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