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Why Mulch Gets Hard And 5 Easy Solutions

Why Mulch Gets Hard And 5 Easy Solutions

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Willie Moore
Latest posts by Willie Moore (see all)

Mulching is essential for your plants. It regulates soil moisture content and soil temperatures and improves your plants’ health. But if you don’t care for your mulch, it will harden or go bad quicker than it should.

Mulch hardens in summer due to the heat from decomposition. Dry mulches become susceptible to fungi colonization, thereby becoming dusty, thick, and matted. This effect causes water to slide off instead of soaking into the mulch, putting your plants at risk of underwatering.

I will explain why your mulch hardens in this article and give possible solutions. Mulching doesn’t have to be challenging or costly. You only need to look for good tips.

Reasons Why Your Mulch Gets Hard

Mulching takes more than putting either organic or inorganic mulching material around your plants. It requires regular check-ups and fixing any problems that come up.

1. Piling the Mulch Too Deep Without Turning

Your mulch may harden if you pile too much and leave it for too long without turning. The mulch will act under its weight and become packed closely together. Eventually, it will become hydrophobic and deprive your plants of adequate watering.

The piled-up mulch will get hot from decomposition during the peak of summer, causing it to dry out. And you’ll have to replace it sooner before fungi colonize it.

2. Mulch Volcanoes

Mulch volcanoes occur when you mound mulch too close to the base of perennials and can be dangerous for their health.

Putting mulch too close to the base of your plants makes them susceptible to attack by insects and rot in case of excessive watering. It also becomes hydrophobic if left unturned for a while.

3. Using Dyed Mulch

Some bagged mulches contain natural dyes, while others may come sprayed with colorants toxic to you and your pets. Some of these chemicals can be hydrophobic or water-repellent when exposed to the elements.

Besides this, when they leach into the ground, they can become toxic to the beneficial soil microbes that help maintain the soil’s health.

4. Using Mulch Mixed With Soil

A good mulching material should allow water to pass through freely. But a mulch can become dry if its pockets are full of soil. The soil in the mulch will take up a good portion of the water meant for your plants.

Remember, the plant roots are underneath the mulch, not in it.

Although you can improve your topsoil by mixing it with compost, the mulch should remain on top. Mixing your mulch with soil will alter the soil’s nutrient composition and deprive your plants of much-needed minerals.

5. Plastic Mulch Exposed to the Sun

Plastic mulch is convenient for warming the soil in spring and minimizing moisture loss during summer. However, it’s more useful over short growing seasons.

Unfortunately, plastic mulch isn’t porous and will make it difficult to water your plants. And when exposed to the hot summer, it breaks down and raises the soil temperature to dangerous levels.

When exposed to the sun, it hardens and breaks down. Increasing the soil temperature evaporates the moisture causing the top soils to harden.

Five Ways To Prevent Your Mulch From Getting Hard

Mulching your garden will help your plants grow, but they’ll be much healthier and more lively if you know a few dos and don’ts for mulching your garden.

1. Not Too Much, Not Too Little

Ideally, you should apply about 2-4 inches (50-100mm) of mulch and not more. A mulch above 4 inches (100mm) will most likely damage a plant’s root system.

Apply 1-2 inches (25-50mm) of mulch if you work with double-shredded or textured mulch. It tends to let less oxygen into the plant’s root system.

Mulching less than an inch (25mm) high will serve no purpose.

Although watering might become much more manageable, it won’t prevent excessive water evaporation. Weeds will penetrate through the mulch easily, and it will be like you didn’t place any mulch around your plants (source).

2. Mix and Turn Your Mulch

Mixing and turning your mulch every growing season should be a common practice to break loose clustered pieces. It will ensure that the mulching material doesn’t form a compacted layer on the topsoil.

Take the following steps to turn your mulch:

  1. Use a rake and a pair of gloves
  2. Rake your garden to break up hardened mulch clumps
  3. Turn over the mulch near young plants by hand
  4. Replace decomposed mulch

3. Try a Different Mulch

Mulches come in several textures, such as pine straw, compost leaves, shredded hardwood bark, crumbed rubber, plastic, and more.

Although you should re-mulch your garden often, you can try a different mulch if your previous one hardened quickly.

Different mulch textures will also give your garden a new look. You can try other options such as dried cocoa bean shells, grounded palettes, seaweed, or nut hulls.

4. Avoid Using Bad Mulch

You might wonder what good or lousy mulch is. And the first step to getting a bad mulch is getting it from an unreliable source. You could pay for it the hard way if it comes riddled with noxious weed seeds. Introducing weeds to your garden is a big no. 

Aren’t you afraid of wasting all the effort of removing foreign plants from your garden?

Avoid using fresh mulch as well. Fresh mulch from pastures and hay fields will most likely contain weed seeds and herbicide residues that can damage your plants. Let fresh mulch sit for a few months before mulching your plants.

5. Re-Mulch Twice a Year

Add more mulch if your existing one begins to thin out. Re-mulch your garden twice a year, once in fall and once in spring. However, you should replace it if it breaks down in your hands. 

Remember to maintain your mulch within the recommended amount—the golden rule: not too much, not too little.

Closing Remarks

Taking care of your mulch keeps your plants healthy and happy. If you notice it hardening, it’s time to check on your mulching practices. 

Avoid heaping too much mulching material around the base of your plants to prevent the material from hardening. Re-mulch your garden twice a year and replace decomposed mulch that breaks down like dirt in your hands.

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