Pros & Cons of Rocks vs. Mulch in Landscaping

Organic Mulch

• Pros

  • Better growth: Mulch doubles the rate at which the trees grow. This is according to a study by Kansas State University.
  • Less water: Mulch will reduce the evaporation so that you don’t spend a lot of time and money watering.
  • More nutrients: As it breaks down, mulch will release nutrients that plants need to grow.
  • Fewer weeds: Mulch will keep weed seeds from growing. You will notice 50% fewer weeds.
  • Regulates temperature: Mulch will keep your plants warm during winter and cool in hot summers.
  • Reduce erosion and compaction: Mulch has been found to reduce erosion by a whopping 85%. People are less likely to step on the mulch hence less compaction of the soil.

• Cons

  • Annual replacement: Mulch has to be replaced once every one to four years. It depends on the type of mulch you are using. This means mulch is a recurring time and money expense.
  • Too much of a good thing: Adding a thick layer of over 3 inches will stress out a plant.
  • Mulching too early can lead to late blooms. When you mulch too early you might slow how fast the ground warms. This might lead to late blooms.
  • Mulching too late leads to weeds: Mulching will keep weeds from growing. However, if you are late in mulching, mulching might not stop the weeds from germinating.
  • Check for seeds: Some of the organic mulches such as hay and pine bark may contain seeds which might grow.

Rocks In Your Garden

• Pros

  • Low maintenance: You will almost never have to replace them.
  • Low cost: Since rocks are long-lasting, they are less expensive to use and maintain than mulch.
  • Fireproof: Rocks are non-flammable hence ideal for areas with wildfires.
  • Can eliminate weeds: Rocks will keep the weeds away much longer.
  • Wind-resistant: Heavy rocks will prevent soil erosion in windy areas.
  • Perfect for cacti and rock gardens.

• Cons

  • Too hot: Rocks, more so the lighter ones, will increase soil temperature thus causing plants to be stressed and thirsty.
  • No benefit to the plants: Rocks will not aid soil health or plant growth.
  • Messy pH: The majority of trees need acidic soils but rocks will make the soil alkaline. This can hurt the trees.
  • Weeds will eventually grow: Weeds will eventually grow between the rocks.
  • Not good for pruning: They can bar rejuvenation pruning leading to unwieldy shrubs.
  • Remove by hand: Removing rocks has to be done manually.

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