Different mulches for gardens

Asked July 18, 2019, 10:38 AM EDT

I’m looking for the chart showing different mulches that are used in gardens. I used pine needles for mulch for years. It’s seems everyone says “ pine needles acidify soil.” The pdf or chart I used to find stated that pine needles used as much added a negligible amount of acidification. Please send and post this information. Could you send me a link to this information! Pine needles are a great mulch if you have a source to gather them from.

Washington County Minnesota mulch mulching mulching vegetable garden

8 Responses

Thanks Pat M,
Can you find the UMN list of mulches the umn put out. It was a list of mulches with comments as to the different traits each mulch had. My wife and I used them (pine needs) for years and loved them. We had a good cheap source. My parents home. It seems like people in general do not know pine needles are a great mulch, but they all know pine needles contribute acid to the soil. I’m hoping for a link to the umn article chart on mulch. Trust me, it’s somewhere there. Can you help?

We could not find a specific list of mulches used by the U.

I looked too Pat. Dang. I’ll dig through some paperwork hoping to find a printed copy.
If I find it, I’ll send a pic.
Thank you for looking!
Mike

Pine needles
Myth
Pine needles will acidify my soil
Fact
Can be used as an organic mulch
Your Logo or Name Here 5
From a u of mn slide show.
Michael r. Anderson

Hi, I’m sorry, but I don’t understand. Were you just confirming the answers from Pat?

Hi Susan,
I had asked Pat for information from the U of MN concerning using pine needles for mulch. Using pine needles is a great mulch. It seems so many people “know” that pine needles contribute acid to the . It’s not true. I sent Pat some thing from a UMN slide show showing that it is a myth than pine needles add acid to the soil. Pat sent me info from Oregon university. An ok answer but not from the Umn. I remember a chart of mulches listed by the Umn that mentioned mulches benefits/ drawbacks. Loved that chart to shut people up about usingine needles for much. Can you find it?

This is the state of science on mulches. The entire article is available here. https://www.researchgate.net/publication/255642668_A_Meta-analysis_of_Studies_Published_in_Arboriculture_Urban_Forestry_Relating_to_Organic_Materials_and_Impacts_on_Soil_Tree_and_Environmental_Properties

Note that all mulches in two of the studies here were found to make soil slightly more acid (page 223, left column, para beginning Treatment effects)
Having used a variety of mulches, pine needles cost more than pine bark. A soil test http://soiltest.cfans.umn.edu/ is best to tell if you need acidification.
Given this kind of information, I buy mulch made from trees based on appearance and price. I do not buy dyed mulches partly because most do not say what the tint is and secondly because tinted mulches are often made of shredded lumber. I do not buy shredded lumber mulches because some contain treated or contaminated wood. https://ag.umass.edu/landscape/fact-sheets/colored-bark-mulch I do not buy rubber mulches because of the abundance of tree-derived mulches and because it does not retain water and because of its permanence.