Friday, September 18, 2009

The Great Mulch Controversy

Back when I was a kid, plants went into the ground, we pulled and hoed weeds all summer, picked the vegetables and at the end of the year it all got tilled under to go back into the soil for next year.

Mulch was an unheard of entity, so I grew up with little or no mulch knowledge or experience.

When we started planting a garden here, I discovered that first of all, I didn't have the patience, willpower, or determination that my mother had, and second, I didn't have a houseful of kids that I could put to work weeding. So I started looking at other options.

Mulch was suggested, but, not knowing anything about it, I was hesitant at first.

But as we got more involved in the garden, I decided to take some time and really research it out.

What is mulch? Why use it? What kind is best? All that stuff.

So here are the results of my research as well as my own personal experiments with mulching.

Mulch is a layer of material covering the soil to exclude sunlight. Since most seeds require sunlight to germinate it is proven to be an effective method of preventing germination and growth of annual weeds.

Benefits of mulching:
• Keeps the soil cooler in the heat of the summer.
• Prevents erosion of valuable topsoil.
• Conserves nitrogen by preventing sun from heating the soils surface.
• Protects roots from hard winter freezes.

Possible negative impact of mulch:
• It provides a cover and breeding place for snails and bugs.
• Wet mulch can cause root and stem rot.
• Exposed soil warms faster in the spring than mulched topsoil.
• Mulching some vegetables too early can discourage growth.
• Organic mulch that is not partially decomposed can rob soil of nitrogen.

Once I had determined that I wanted to mulch my garden, weighing the pros and cons carefully, the next step was to figure out what kind of mulch to use.

I looked at several options:

Hay and straw: Allows good water penetration, may contain grain seed. Can mold and mat in
wet weather.

Pine needles: Adds acidity; pine resins may be toxic to some plants.

Grass clippings: Readily available, can reapply over time, may contain weed seeds or bermudagras rhizomes, may mat and reduce water penetration if not dried first.

Compost: Excellent source of organic matter; may harbor certain weed seeds or plant pathogens if not properly prepared.

Newspapers (shredded): Readily available, low cost, no weed seeds, attracts earwigs, sowbugs, not stable in windy locations.

Newspapers (folded): attracts earwigs, beetles, sowbugs, not stable in windy locations. Requires compost or other weighted materials to hold down.

We don't really have enough grass clippings or compost to do the trick. But we do have a whole lot of wind. Living right on Lake Erie, we have the wind off the lake that can be pretty heavy at times.

So we were in a quandary.

Finally, we decided we would use sheets of newspaper, and the cover them with something to weigh them down.

Now, here is the other factor. Our herb garden is the first thing anyone sees when they walk up to our front door. I'm not nearly the artistic gardener some people are, I look at Sue's Corner Garden for example and I know that I will never have a garden that looks as good as that. But we do take a certain amount of pride in the way the garden looks and we wanted to make sure it looked nice.

Our first instinct was red mulch. When I first started researching it, I was amazed at the controversy out there.

Some people don't like it because of the way It looks, others because it takes too long to break down, thus depleting the oxygen from the soil.

I read one blog where, and I kid you not, a woman told a story about her neighbors using red mulch. She knew that some dyes were harmful, so she took some of their mulch and put it in a jar of water. Sure enough, it turned the water red. Armed with her jar of water, she marched over and confronted the teenage kid who had just spent all day putting the mulch down. She gave him her whole spiel and made him feel guilty for using it.

I was amazed that someone would go on such a crusade, prepared with so little facts, but I shrugged and continued my research.

There are clearly advantages and disadvantages to using red mulch:

• The contrast of the red, against the green of the plants is very attractive.
• The red color is actually beneficial to plants. As the sun reflects off the red, it gives the plant the illusion that there are other plants very close to them. This causes them to grow stronger and healthier, because they think they have to compete for water and nutrients.
• The Iron Oxide that the mulch is dyed with, will seep into the soil, providing valuable iron to your plants.

• Wood chip mulch takes longer to break down than straw or grass.
• Wood requires nitrogen to decompose, so if you don't add nitrogen, the mulch may deplete nitrogen levels in your soil. (Note, if this is a concern, poultry manure is an excellent source of nitrogen.)
• Some wood chips are made from recycled scrap lumber. If your mulch is made locally, make sure you buy mulch that does not contain treated lumber, as the chemicals in the wood can harm your plants, your soil, and leach into the water table.

There are a few things to keep in mind when and if you choose to use red mulch:

• Make sure that you use Mulch that is stained or Dyed with Iron Oxide, and not with chemical dye.
• Make sure that you aren't using chipped wood made from treated wood.
• Cedar mulch will break down faster than many other mulches, but natural cedar is not as deep a red as dyed mulch.
• Cypress mulch used to be made from mill by products, but now cypress trees are harvested just to make mulch. Is depletion of habitat swamplands really worth a few weedless gardens?

So, again we weighed pros and cons and went with the red mulch. We used a mill
by-product mulch dyed red with iron oxide stain.

I wrote a blog post early in the year, when we first added the newspapers, you can read that here: Weeds .

Throughout the course of the year, I have had to pull a few weeds, mostly from right at the base of our plants, where they had grown through the holes I cut for the herbs. But other than that, we have enjoyed a weed free, and relatively maintenance free herb garden.

We have spent over seven weeks since the first week of April away from home, enjoying the summer, and enjoying our travel trailer. Our flowers suffered, but our herb garden flourished.

I also put newspapers and red mulch in the flower bed, with a somewhat less positive result.

I think I figured out what my mistakes were though.

Over the last few years, we have added quite a bit to our flower bed, and although it is a raised box, the level of the soil in the center was about 8" higher than the sides of the box. I took out quite a bit of soil, moving it to where we needed some, and it didn't occur to me until to late that I had taken all the nutrient rich soil from the top away and left the lower quality soil in the bed. Next year, I will make sure and enrich that soil with some good organic matter, and bring some life to it before we plant it.

The flower bed also gets a lot more wind than the herb garden does, and the mulch blew away and dried out. This resulted in big spots of newspaper as big as my hand exposed. Next year, I need to create some kind of wind break around the border, either by planting something, or maybe just adding some decorative edging of some type.

So, here's our mulch report for the year.

We used newspapers on top of the soil, then covered the newspapers with mulch.
We had virtually no problem with weeds all year, watered far less frequently than we have in years past, and our garden still looks great.

I will definitely be using newspapers in the future. My choice of mulch, on top of the papers may vary, based on availability and aesthetics.

1 comment:

  1. Thankyou! You definetly had me in suspense--I'll continue gathering my newspapers.