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Vanilla Technical Session | What is Mulch?

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Coconut husks over lava rocks can work as a great mulch for vanilla IMAGE: Diomari Madulara

By Piero Bianchessi, Former Owner and Operator of Venui Vanilla

What is Mulch?

Like leaf cover in a forest, mulch is a layer of mostly organic (or occasionally inorganic) matter placed over the soil to:

(1) Retain moisture

(2) Aerate the soil

(3) Provide nutrients

(4) Increase the biological activity of micro-organisms and beneficial root-associated fungi

(5) Protect the roots from the sun and maintain low soil temperature

(6) Control weeds

(7) Reduce erosion


Vanilla ground-roots thrive in old, well decayed and aerated soft mulch. Vanilla roots buried in soil tend to rot unless the soil is very rich in humus.


  • – Rotting tree bark
  • – Coconut husks
  • – Cocoa pods
  • – Peat moss
  • – Wood chips
  • – Oil palm waste
  • – Black fern pieces
  • – Decaying wood
  • – Charcoal
  • – Sugar cane straw
  • – Seaweed
  • – Well composted leaves

Depending on the material used some mulches decay (compost) very quickly (i.e leaves and grass) while others are relatively long lasting.


Green or un-composted matter for mulch in a vanilla plantation including:

  • – freshly cut grass
  • – green leaves
  • – un-composted kitchen waste
  • – fresh coconut husk/cocoa pod
  • – freshly cut sawdust

Avoid material prone to form a soggy mat when wet (i.e. some leaves, grass clippings, and fine sawdust). Only use these materials if well composted and intermixed with more rough and bulky material such as coconut husks and decaying timber.


Mulch should be approximately 20cm thick above the soil surface and cover an area 1.0 meter in diameter around the plant. New mulch must be regularly added all year round and every time a vanilla vine is looped.


A few inorganic mulches like porous clay, light porous lava rocks, etc offer long lasting protection BUT DO NOT provide nutrients. Mix these with organic mulch.

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