Growing Lots of Ginger : is this the best mulch?

giger crop

All plants will benefit from mulch to help retain moisture and to keep weeds down. While growing ginger and using a particular mulch, we stumbled onto what could be a great mulch, if not the best.

We live in the tropics, and ginger can grow like a weed. There are spots in the yard where ginger is waiting for the right temperature and humidity to push up spears of fresh stems of rolled-up leaves, but you wouldn’t know it in the dry season.

The garden bed looks empty, with the only hint of what is below the surface being the remnants of last year’s dried-up fronds lying about. This leads us to “forget” about the ginger because it is not in your face waiting to be harvested. There is more detail on this in “growing ginger.”

We sometimes plant out beds with the intention to harvest them at the season’s end, and it was one of those times that changed how we grow ginger. To get to the rest of the story, I have to set the scene.

ginger harvest
The end result of a 1 x 4 meter bed of ginger. Almost 50kgs all organic. Check the prices in the shops.

How to make Great Mulch.

We have a side gig.

If the sub-heading above has you thinking we make and sell mulch, you would be wrong. It has only a little to do with mulch, and even that is just a byproduct of the gig.

We make and sell wood products at a local market/fair.

We start with donated logs, slab them with a chainsaw mill, then stack and dry the timber slabs until they are dry.

We have several wood lathes; with these, we turn items we sell to customers. It works out well as it allows us to continue working on the yard and writing when a thought takes us.

We had a period a year or two back where we had a heap of rain over a few weeks that softened the soil, and this was followed by some powerful winds that were out of the ordinary.

This wind brought down many trees, and we were donated some local acacia logs. This wood is a wattle, one of the many we have in Australia, and this tree is a pioneer species meaning it is an early grower on the edges of cleared country. It is fast-growing and short-lived and is also a legume.

Legumes are well known for fixing nitrogen into the soil at the root level, and being a pioneer, the tree is known for being a miner of minerals.

This information is vital to remember as it is the basis of this whole article.

The actions of the wind set in motion the natural creation of good soil via the rotting down of the logs that were full of nutrients and minerals, but we stepped in to take the logs before the decay process started.

We decided to turn wooden bowls out of one of these logs while the wood was still wet with sap.

I spent a few days rough turning the bowls while the juice from the wood was spraying me and the lathe as it was spinning.

The juice is very corrosive when it contacts steel.

This is notable because it suggests the sap/juice is acidic, and acids help break down minerals and organic matter, so maybe you can see where this is headed.

I ended up with a few wheelbarrows of fresh, damp, wood shavings to put on the garden.

wood shavings under a lathe with bowls rough turned in the mulch to keep them from drying out to fast.
Image cut from video. Apologies for the quality.

Preparing a garden bed for ginger.

After a few days of wood turning, we set out to prep the garden bed that was between two guavas.

We grabbed a garden fork and lightly turned the soil over, noticing a few worms and plenty of smaller life forms running around in the soil.

We spread a little chicken poop, planted the bed with ginger rhizomes that had already started sprouting and covered the bed with 100mm or 4inches of wattle shavings.

This is all we did to the bed. We watered the bed for the first few days, then left it alone over the wet season.

We had no idea what was going on in the bed as we went about our days planting other things, making a few timber products for customers, and generally keeping busy.

What makes a good mulch?

Good mulch allows moisture to pass through from above while limiting the water loss from the soil through evaporation and the best mulch feeds the plants and soil simultaneously.

I had never given much thought to mulch. It was a consumable item in the yard, and it was there to keep moisture in and slow unwanted plants down from taking root.

I had never considered it something you could enhance or supercharge, but the ginger and the wattle have taught me differently.

What happened, and you will pick up on this pretty fast, is that because I wet-turned the bowls on the lathe, I did not remove the sapwood from the log. It was included in the bowls, or some of them, at least.

The sapwood is pale against the darker browns and golds of the heartwood. But the lesson here is that much of the sapwood was part of the shavings that went onto the ginger bed.

Sapwood is where the tree transports the nutrients up and down the trunk as it grows, and a good analogy is the heartwood is the bone, and the sapwood is the artery.

So, this sapwood was loaded with minerals and was also very acidic. We know ginger grows well in slightly acid soils. Things were lining up nicely, but we had no idea at this stage.

The rainforest up this way has many varieties of flowering gingers that grow prolifically, and rainforest soils are generally acid in pH.

They all grow in similar conditions to the ginger we are talking about in this article, but getting back to the mulch and the acidic conditions we unwittingly created, it all makes sense to me now. I stumbled onto what could be the best mulch for growing ginger.

We lifted that bed at the end of the season instead of leaving it for another few years and having the rhizomes slowly age and decay.

The amount of ginger we harvested was astounding, and some of the rhizomes were as big as mud crab claws. We didn’t fertilize the bed other than a little bit of chicken manure from the chicken pen at planting time.

We didn’t treat the soil with anything other than the mulch. To get an idea for an average return, “How much ginger can one plant produce?” details an average crop. This article you are reading is anything but average.

My theory is that the minerals locked up in the sapwood made their way into the soil through the mulch, and during the wet season, the rain activated the acids in the sapwood to help release the minerals into the soil.

The next surprise was the number of worms in the bed. They were huge by our standards and were often entangled amongst the ginger rhizomes. They took some getting out.

ginger harvest in the sun
All organic. 4 m2 or 43 ft2 of bed

Making more mulch.

We plan on repeating this process when another log comes our way, and it will be interesting to see if the theory can be confirmed with duplicated results. By the way, this entire process should be effective for all edible ginger varieties. If you want a curated list of gingers where the whole plant is edible, “5 types of edible gingers for a self-sufficient backyard” could be for you.

We love the experimental side of Permaculture, and this is one of those events that make one realize just how little we know about living systems in the soil.

Ginger is one of our Resilient Food Plants that we rely on every year.

Article by Tim Blanch for He is a qualified Permaculture designer.