by Kathleen Rieman
“So, tell me, what is it with mulching?” a good gardening friend, a ‘sister in the soil,’ Shari, asked me recently, as we were planting a second crop of salad greens in the 85° that had given us an early May, Rogue Valley warm up.
“Every garden article I read, every nursery I shop at, and you tell me it is the way to keep our gardens alive and healthy, use less time gardening, conserve water, and save our backs. So, convince me I should bother with mulching.”
“Yup – that is all true. The benefits definitely outweigh any effort required and make mulching eminently worthwhile. In more than 4 decades of gardening I have become a true believer.” I answered, as we headed to the shade to discuss the matter further.
I took a deep breath before I launched into a list of mulching benefits. I listed only the ‘pluses’, because the other side of the equation is just too trivial to oppose the benefits.
How Mulching saves your back, water and time, and produces healthier gardens:
- It prevents evaporation of water from the soil. Plants are healthier when they don’t dry excessively between irrigations.
- Mulching reduces weather induced stress to garden plants by maintaining a more even soil temperature – cooler in the summertime and warmer in the wintertime.
- It prevents germination of weed seeds (if your mulch is free of weeds and is laid down deeply enough). It will also impede some existing weeds – but it’s best to lay mulching over an area free of weeds to start with.
- Mulching helps to control soil erosion and stops soil diseases from splashing onto plants.
- Mulching helps to maintain better soil structure and aeration by preventing compaction. It also can improve soil structure as it decays, adds nutrients to the soil and actually becomes part of the topsoil.
- The use of mulches results in garden plants with more robust root systems because additional roots will grow in the mulch around the plants.
- Mulching soil around garden plants minimizes crusting of heavy soils (most of the Rogue Valley). Preventing soil crusting aids water absorption and aeration, resulting in less need for cultivation in the garden.
- Well applied mulching can enhance the appearance of the garden and landscape: a consistent color and form around garden plants provides a unifying element to the yard and sets off individual plants.
“Okay,” said my soil sister, “I now believe, and I promise to start mulching!
But what do I need to get started with this mulching?”
“Well – here’s the great news about mulching,” I told her, “Mulches can be almost anything!” However, it is true I have worked for Grange Co-op for several decades, and I have some definite favorites in bagged mulches.
My favorite Mulching materials:
- A nice choice is Green Planet Naturals Compost, in a 1.5 cu ft bag, all-natural and produced locally in the Rogue Valley. The compact bag makes it easy to haul and use.
- One of my favorites is Gardner & Bloome Soil Building Compost that comes in a 3cu. ft. bag. This product is based upon composted, shredded wood waste. As it breaks down, it really does enhance the condition of the soil. I love this stuff!
- Shasta Soil Conditioner, available in a 3 cu. ft. bag, is an attractive black-brown, with the consistency and appearance of coarse coffee grounds, and is comprised of bark fines. It has been treated with Nitrogen to compensate for the nutrient drain on the soil as the bark fines break down. This is a very economical mulch choice.
Some other great mulching choices:
- Wood Chips – available in different sizes. These will take some nutrient out of the soil as they decompose, so extra fertilizing is a good idea.
- Leaves – layered several inches deep after being shredded (use your lawn mower), leaves do a good job. They’ll breakdown and eventually build your soil.
- Grass Clippings – make wonderful mulching in the lawn, and dried out grass clippings are useful in the garden if added an inch or two at a time; thick layers of fresh clippings are not a good idea. Avoid clippings containing any weeds!
- Pine Needles – can make excellent mulching around acid-loving plants such as Rhododendrons, Blueberries, Azaleas, Ferns, etc. Again, use only a 2-3” layer around garden plants – don’t rake up the forest! Dried pine needles could be risky if you live in a fire prone area.
‘Structural’ mulch options:
Almost any inert material could be used as mulching – with greater or less degrees of appeal and desirability. Any of these items could be used:
- Gravel, Stone
- Plastic, clear or black
- Landscape fabric – woven to permit penetration of water and air. Great for weed control in difficult areas. Usually used with wood chips or gravel on top to keep the material in place and improve appearance
- Layers of plain, black and white newspaper. Colored newsprints carry chemicals and heavy metals you may not want in your garden soil. Not an esthetic choice, but very economical and effective – especially in a backyard vegetable garden. (The newspaper also provides a great way to trap earwigs!)
After having listed all the benefits and materials for mulching, I had nearly exhausted my garden buddy. But she bravely persisted with questions about “how to do it.” I let her know that Mulching is really quite simple in application – with only a couple of absolutes to remember:
- The best time to mulch is right after planting. Established plantings benefit from spring mulching, and for winter mulching – wait ‘til frosts have started.
- It is best to weed the area first, so you won’t have to use up your back weeding again and again.
- Cover the root zone of the plants, but do not pile mulching up against the base or stem of your plants. You will prevent rot from excessively wet mulch, and the possibility of rodents overwintering in the mulch and damaging your plants.
- The Azalea, Heather, Blueberry family (Ericacea) is special – these have very wide and shallow roots, that hate mulch around their stems. Keep mulches about 4” away from the trunk or stem, but cover the root zone with a good layer of mulching at least a foot out from the plant’s drip line.
My new mulching convert was not prepared to contemplate the topic further at more than 85°, so I promised to send her this little guide. And, as she took her tools to escape the heat of my garden schoolroom, I reminded her Grange Co-op’s garden centers could help her calculate exactly how much mulch she needed to save water, time and her back this season.
And that, dear Shari, is what “it is with Mulching.”