Making Soil From Clay (Miracles Do Happen)

Broccoli seedlings

The end of winter/ beginning of spring is a telling time in the garden because soil is at it’s most saturated.

How goes your soil?

  • If it’s wet (as in fashion a pot from it wet) then you’re still in the building phase, not quite at the cropping phase.
  • If it’s so wet your steps squelch and/or you can see water, then you’re gonna need to put your thinking cap on and find a way to drain that water away. Or perhaps choose higher ground for the vegetable patch. Water displaces air, and air is what we seek.

Claggy clay is a mission to improve, at times a disheartening one. Like a grouchy teen, it’s best left alone when it’s at it’s soggy worst, playing with it in this state only makes it worse. Meantime grow your crops elsewhere in tyres, pots or bales of hay until you’ve created some decent soil.

The bonus of clay is the mineral richness just waiting to be unlocked. Transform it with these three things – air, organic matter and time.

Here’s How

Once the bed’s dried out (no puddles, no sound effects), aerate with a handy dandy forksta (my favourite tool ever) or broadfork or go hundy and double dig. Lightly work in a thin layer of compost and gypsum. Then sow a pea/ oat or lupin greencrop.  Chop the lupin down just as it gears up to flower.

This is the beginning of great things – not the end of the road.”How long is this road?,” you are going to ask me (I know you so well!). This depends on so many things (yes, you know me too!) – the type of clay you got going on, what’s beneath that clay, and how attentive you are.

yummy soil

It can seem endless this transformation, but have patience. If your soil is still heavy and barren after the first greencrop, hold off on the cropping and do one or other of these things

  • Go another round with your forksta and a different greencrop.
  • Trench your foodscraps up the middle of the bed and pile mulch on top, leave it.
  • EM is awesome! Get a microbal tribe on your side
  • Build a row of compost piles on top of your bed.

Soon you’ll see a change in colour and an increase in earthworms, you’ll feel a loosening of the texture, smell a sweeter smell and for the brave, the soil will loose it’s tangy taste.

Take heart and keep on keepin’ on. Loam wasn’t built in a day!


  1. Absolutely loved this post Kath, thanks heaps! I’m not sure if I’m brave enough to taste soil yet but I’m tempted after your post!

    • Go on Sophie! You can do it! Just a little on the end of your tongue – don’t gulp it back, just taste it and spit it out. It’s amazing how good (oh lord am really putting myself out there now) good healthy soil tastes (the opposite is true as well :)) A bit of parsley afterwards is the thing…..

  2. After learning to garden on sand, I bought a property with compacted clay on the flat. What a different world that is. I have found double-digging transformative. I know it’s out of fashion and no-till is the mantra with many/most permies and organic types but I saw with my own eyes the incredible soil structure Jodi Roebuck had developed on clay soils in Taranaki. He’s trained extensively in the GROW Biointensive method with John Jeavons. I applied what I learnt in establishing my own garden beds (along with gypsum and Environmental Fertilisers inputs) and the difference is amazing. It’s squelching down there at present after sustained rain and I’m keeping off the lawns as much as possible. But I know those beds are better drained than the lawn around them. I have made mistakes — the first double digging was done too early in spring and before the soil had dried out enough. I’ve learnt my lesson and am learning patience — the soil is to be worked when IT is ready, not when I want to. Three years in, I’m encouraged. I know there are other methods that work; the use of deep rooted cover crops you’ve described sound like a good alternative, one that involves less sweat. Anyway, thank you for more good advice Kath and I just want to encourage anyone else reading this: clay comes good. And I’d choose it over sand any day.

    • Thanks so much Rachel for taking the time to share your tale of encouragement! Gardeners on clay can’t have too much of it. Double digging (thanks for bringing it into the conversation) is indeed the business when it comes to transforming clay (is it really considered old fashioned? I’m hoping it’s the other way round …. no dig = old fashioned, opening soil = high fashion.) Those of you who’s ears perked up at the mention of double digging do check out Jodi Roebuck/ John Jeavons.
      I love and adore my broadfork and the wonderful work it does opening my soil, grateful too that it allows me an out from the big work of double digging. Oh lord that sounds lazy :)!! Were I truly committed I’d use both, I know. As you so rightly say – many roads lead to Rome, and because the gifts of edible gardening go beyond the good food, it’s so important to do it the way you love, don’t you think.
      all the best Kath