An Introduction to Garden Mulching
We talk about fertilization a lot here, but I would like to take the opportunity to write on the benefits of mulch in your garden. This is a complex subject, but my goal today is to provide you with a basic introduction to garden mulch. Mulch is simply a ground cover. It can be either organic or inorganic matter. However, today I am primarily talking about natural mulches. I believe they are a better value for gardeners because they feed the soil. Sure, you have less maintenance with shredded rubber mulch. I guess you could even technically say it’s organic since rubber comes from a tree in some cases. The problem is that you are missing one of the many benefits of mulch, carbon breakdown. Today we are going to learn the benefits of natural mulch and explain how to add nitrogen to mulch.
How Mulch Adds Nutrients to the Soil
Carbon found in soil is a good sign that there is life in the soil. Bacteria break down carbon from natural forest mulch. They convert decaying leaves, straw, and limbs into nutrients that feed living plants. Additionally, any sources of nitrogen tend to bind with the carbon in mulch. This makes it eventually become available to plants as the microorganisms do their work. In fact, you can greatly benefit your soil conditions by adding a little nitrogen to your mulch before spreading it. So, remember that mulch breaks down slowly over time. If your plants need nutrients now, you should apply a quality liquid fertilizer.
Added Benefits of Mulching
In addition to providing nutrients, mulch protects the soil from many things that should concern the experienced gardener. Wind and rain erosion are best controlled with a layer of mulch. Weeds are also much easier to manage. You don’t have too many seeds with the energy required to break through the mulch before dying. Moisture retention is improved, and well mulched soil protects plants from temperature swings.
Less Irrigation Requirements
Irrigation can be a major concern for gardeners. Here in Alabama, we experienced a historic drought in 2016. My property went a full three months without rain. You could see a marked difference between the trees that we mulched versus those without. Mulch limits evaporation from the soil surface. It also helps with the even distribution of irrigation by slowing down infiltration. If you soak an area without mulch too fast, it is easy to create a surface run-off event which will leach nutrients downhill and rob your plants of food. Mulch helps with water management and may reduce your irrigation costs.
Nitrogen Loss Concerns with Mulch
When you are working with an organic mulch, bacteria tend to lock up the small amounts of nitrogen present at the surface. For this reason, you should never till in a high carbon mulch. Tilling in wood chips or leaf clippings will temporarily cause a nitrogen deficit. Simply placing mulch on the surface only allows the bacteria access to the very top layer of nitrogen in your soil. So, the temporary deficit there will not really harm plants with deep roots. If you want to add a bit of nitrogen to your mulch, it will be great for your plants. Keep reading and I will tell you how to add nitrogen to mulch before spreading it. However, be warned that your mulch will break down faster. So, you will be reapplying mulch much sooner with the method listed below.
How to Add Nitrogen to Mulch
You will need at least a 300-gallon stock tank to treat a cubic yard of mulch. If you don’t have a large stock tank, you can always scale this down. Just be sure to also scale back the amount of fertilizer used. This method will work great with any high carbon mulch. Fill your stock tank with wood chips, straw, shredded leaves, or cocoa mulch. Dilute two quarts of Neptune’s Harvest Fertilizer with water in a 5-gallon bucket. Be sure to stir in the fertilizer well. Pour this over your mulch you added to the stock tank. Next, go ahead and fill the tank up with water. Let this soak for 24 hours, and be sure to stir if possible. The carbon in your mulch should pick up a large amount of nitrogen and other minerals from the fertilizer. Spread this treated mulch around your garden. You can also use the remaining liquid for fertigation. Feel free to share this info on how to add nitrogen to mulch with all your friends!
How Much Mulch Should a Gardener Mulch if a Gardener Could Mulch Mulch?
Like many things in gardening, the answer is IT DEPENDS! Generally, 3-4 inches of mulch is a good rule of thumb for most locations. In locations with heavy clay soil, you can cause too much moisture retention by going over 3-4 inches. In sandy soil, you might increase to 4-6 inches of treated mulch to limit runoff and slowly build nitrogen back into the soil. The most important thing I can tell you is to observe and interact. Wait a week or two after adding your mulch, and pull it back to inspect the soil. If it is soggy, you might have too much in that area. If it is moist but not too wet, you are probably okay. Remember to scale back your irrigation as appropriate. I find that I only have to water my garden about once a week here with mulch. In July if we have little rain, I might increase that to 2-3 times a week.
A Final Word on Mulch and Soil Health
I just wanted to take a moment to wrap up this post with a word on soil health. When we do soil analysis for farmers to help them pick the right application of fertilizer, we test for carbon. Higher levels of carbon usually indicate that the soil is full of life. Mulch is a great way to create an environment that is friendly to healthy soil microorganisms. Not only will you attract microscopic life, but you will also bring in earthworms and other beneficial insects. Over time, this will reduce your dependency on fertilization.
An acre of healthy earthworms can produce up to 700 lbs. of worm castings each day! Worm castings vary in fertility based on diet, but a common number is 1-1-.5 according to the NPK ratio. In addition, calcium, magnesium, and other micronutrients are present in worm castings. So, feed the worms with mulch and you feed the plants. While they are busy converting mulch into fertilizer for you, they also aerate the soil. So, why till when you can mulch and let nature do the heavy lifting? You can often skip tilling for a year or so with mulch. Some gardeners even skip tilling altogether in favor of a deep layer of mulch.
So, now you know all about the many benefits of mulch. You’ve learned how to add nitrogen to mulch to increase breakdown. Be sure to add mulching to your garden or orchard for healthier plants and LESS WORK. You’ll be glad you did. Visit our store to stock up on AGGRAND fertilizer so you can inoculate your mulch with nitrogen before spreading. Happy gardening!