Breaking down the clay! - What to use

[izinoz]

I live in an area of NSW where there is clay about 12'-18' below the surface. I am shortly going to be ready to plant quite a lot of young trees and other shrubs and I had thought of using some gypsum when digging the holes to help break down the clay but someone has told me that it kills worms. I have also heard that dolomite will do the same job but does anyone know whether this is safe for worms and other creatures in the soil?

[gardenlen]

g'day,

i don't know that gypsum kills worms i've used lots of the stuff in different gardens and always had huge populations of worms. dolomite as far as i know is used to alter ph so should be used only when and if you need to do that, you can't overdose with gypsum.

when planting in clay like that i usually dig a hole about twice the size of the pot the plant is currently in, dig it larger if energy permits, then i throw some gypsum around the hole and begin backfilling with a good medium as i plant the tree, then water in well and mulch therafter. never had any failures this way.

if the tree requires better drainage then you may have to create a mound using the same process and plant the tree higher so it's roots aren't down in the sodden clay zone.

if you are going to put garden beds in consider using raised garden beds, too much back breaking work trying to work clay.

len

[Mont]

Izinoz, I've got the same kind of soil as you and I agree with what Len says.

[makehumusnotwar]

i have to agree as well. no point breaking your back and disturbing the soil unnecessarily. build on top by adding humus from your composting, hay, then plant support plants/trees especially the cut-and-drop nitrogen fixers and herbs. then, before you know it, you'll have lush rich soil.
the permaculture principle i'm really trying to implement myself is energy conservation, and working with the land not against it. preferably with items you already have or have produced on site. so many times i've ended up with aches and pains, an empty wallet as well as many car/trailer trips back and forth. now i'm spending more time sitting, observing and pondering. the results are often better anyway, and required nowhere near the physical and financial suffering.

[gardenlen]

couldn't have put it better myself 'makehumusnotwar', excellant,

and some of those nitrogen fixers are:

Leucaena - ‘Leucaena leucocephala’
Pigeon Pea - ‘Cajanus cajan’
Tree lucerne - aka Tagasaste – ‘Chamaecytisus palmensis’

with these they act as close wind/frost breaks for vege patches or around new food trees, they drop leaf litter, or you can pruned and add this to compost rows or garden beds or even shred them and do the same.

also cover crops using any of the legumes or clovers but have a look at these:

Wynn cassia, Round-leaf – ‘Chamaecrista rotundifolia’
Lotononis – ‘Lotononis bainesii’

especially plant those in among the grass you may be collecting for mulch purposes, value adding.

and don't forget the plant everyone loves to hate the black acacias - Acacia leiocalyx.

i have a large list of legumes for the sub-tropics available so if wanted i will post the list here for all to make use of.

len :)

[Peter Warne]

Hi Len - I'd like to see that list of legumes for sub-tropical reasons
Thanks
Peter

[Peter W]

I meant to say sub-tropical regions of course.
Peter

[izinoz]

Thanks to each of you who contributed to my knowledge. Very grateful for the information and I too look forward to seeing the list of nitrogen fixers you refer to Len.