Wood chips instead of rock mulch for a cactus garden

Question

I live in a Mediterranean climate. My soil is light in clay, so it is somewhat sandy. Still, when it's low in organic matter it hardens when dry, since it has some clay in it. The said area has: Parodia Leninghausii, Sansevieria Cylindrica, Echeverias and Aloe hybrids.

My plan: use wood chips mulch, which has some advantages over stone mulch:

1- degrades slowly by fungi, which release some nutrients to the plants and enhance microorganism activity,

2- Less hassle while doing maintenance work, like moving or introducing plants. Easy to rake the work area,

3- porous, allows air and water, though aeration is slow. Chips that were left after raking do not block air and water, because they degrade, while stones accumulate over the years.

4- slugs may feed on the decaying chips, leaving my succulents alone.

So, would my succulents do better with chip mulch than with stone mulch?

Answer 1

You may be able to have the best of both worlds when it comes to mulch. This idea works, but depends on a large extent on the size of the garden (the larger, the better).

You could use wood chips as the basic mulch in the bed, but NOT around the crowns of your plants. Around them, use small rocks/pebbles. It's like putting small doughnuts into a larger area. This should illustrate what I mean (brown = chips, gray = pebbles, green = plants):

The pebbles keep the crowns of the plants away from organic material, which prevents crown rot.

Since you're not using landscape fabric, it's easy to scrape away the chips (as you noted) to add plants, and it's also not too difficult to move the pebbles aside to replant if you lose something.

Please do not use bark here, but use arborist wood chips if available.

Answer 2

Yes, you can use chipped wood, but chipped bark is a better alternative to chipped wood. Chipped bark breaks down slower, less likely to rob your plants of the nitrogen they need. Certain microbes break down organic matter, they feed off the nitrogen in the soil. If your wood is breaking down fast you will have an explosion of microbe growth. This explosion will not only rob the nitrogen from the wood chips, but the soil as well. The wood chips will have very little chance of being a soil conditioner.

I am uncertain what kind of access you have to ground bark. In Canada and the States, we would use primarily pines and fir. (The primary fir is Douglas Fir, which is not even a fir, an Abies, but Abies does work for your application. I believe you have better access to pine bark. Many people also use aged hardwood bark as well. Both barks have positives and negative. But, neither is necessarily better than the other. Hardwood mulch will leave the soil more alkaline and conifer mulch will leave the soil more acidic.

Rock is a pretty horrible mulch. It provides nothing for the soil. It allows weed seeds to get in between the stones and grow. It's impossible to pull up the weeds, roots and all if there is rock in the way. Yes, it does make adding more plants more difficult as well.

You are wrong on the slugs. If anything you will have more slugs. They will be able to hide under the mulch in the hot day and come out to feed at night. All mulch, even rock will give slugs a better chance of creating damage. If you had choose between eating wood or a nice juicy aloe plant, what would you choose?

If you can find ground bark from a conifer plant or aged hardwood. This does not mean you can not use wood chips. You can still use wood chips. You will just need to provide a synthetic fertiliser with high nitrogen content, like lawn fertiliser. Something with a nitrogen rate of 20% or more during the growing season.

If you have any more questions please ask.

Answer 3

Depends how much rain you get - if you live in an area where it doesn't rain often, but when it does, it rains heavily, or alternatively, it rains quite often but its more showery,both wood and bark chips aren't such a great idea compared with stone chippings because they hold onto moisture and take a while to dry out. Plants such as echeverias are shallow rooted, and wood chips might be too damp for them when it rains, though you might get away with a light application of wood chips around deeper rooting succulent plants. https://www.mybluprint.com/article/tips-for-growing-succulents