The Healthy Soil Project #2: Sort Drainage + Compaction

For soil to be in good health, water and air and roots must be able to easily flow through. When they cannot because of compaction or poor drainage, soil health never quite lands.

Compaction is generally an easy fix, and mostly drainage is too – though not always. For gardens on a high water table, in the inner city surrounded by concrete, a low point in a high rainfall zone or a slippery, heavy-duty clay – grow on your highest ground as well as doing all the things I suggest. I don’t often recommend raised beds, but if drainage cannot be resolved – they are the way to go.

How to sort drainage

Drainage is absolutely key for plant health. Our crops must have oxygenated soil to be at peak performance. Water displaces air, you see, so if your soil is soggy, it is also airless. Soil biology thumbs its nose at conditions such as these, and herein lies the deep reason for the drainage – without soil life, there cannot be above ground abundance.

Start by soaking up excess water in trees and plants a la natures way – what a difference!

Tag team that with redirecting excess away from food growing areas in simple mulched drains (aka paths). With both those sorted, drainage will start to improve, and will continue to do so as soil improvements kick in.

Simple Solutions For Too Much Surface Water

Sort soil compaction

In healthy soil, tree roots and tap-root plants and soil biology keep soil open and prevent compaction, but where there is a hard-pan or compacted layer they cannot. Poor drainage and compaction often go hand in hand.

Kickstart de-compaction in your food growing areas, by aerating the soil. Then plant it up right away with fast growing companion trees and lots of tap root companion plants before soil settles back down again. Roots are the long-term answer to de-compaction.

• In a small garden use a forksta, an NZ made long tined fork. It’s light and super easy to use – simply stand on the bar and use your body weight to drive the long tines in, then pull it back towards you to open up the soil. Repeat this action over the area you’re about to plant up.
• On a large scale use a single tyne soil ripper.

In the vegie patch

There are two strategies at play here: a good start as well as ongoing aeration.

A good start: Aerate the whole area, then plant up the outside edges of the vegie patch with a mixture of deep rooting shrubs, berries, dwarf fruit trees and perennials. In a large garden, plant strips up the centre too. Plant a mixture of companions with a focus on tap roots like dandelion, comfrey, chicory, parsley, bishops flower or daikon that open and aerate soils.

Ongoing aeration: Chances are you will need to continue to aerate garden beds for a good few years to come. Do so once or twice a year from when soils dry out in spring through till autumn. As companions stretch out their roots ever deeper, and soil health builds the need will fade away.

Around fruit trees

As far as fruit trees are concerned, aerating is a one-off thing that helps fruit trees get their roots down and out – wide-ranging roots are key for tree health. Companion plants will drive the transformation home.

• Plants lots of tap root companions beneath your fruit trees.
• Plant fast growing companion trees like Italian Alder, Tree Lucerne, Silverberry, Goumi berry, Brush wattle or Tithonia – choose ones that suit your soil, climate and height requirements. Use these as shelter and/ or plant amongst fruit trees. Keep them in check by chopping and dropping limbs for an awesome soil improving mulch, or when they start to get too big, remove them (leave the roots in!) and mulch them up.