Has anyone dyed soil successfully?

[peterbone]

I mainly use a molar clay cat litter product here in the UK (Sanicat pink). However, it's a light pink colour when dry and I'd like something that looks more like akadama for top dressing, without having to pay for akadama. Has anyone had any luck dyeing this kind of soil or similar such as Turface? I've tried coffee, but that didn't seem to have any affect at all. I've looked into a few other options but each one seems to have a problem. The dye needs to stain the soil particles without washing off from watering or bleaching in the sun. It also obviously can't be toxic to the tree.

Home made wood stain from steel wool and vinegar. Vinegar is too acidic.
India ink (lampblack). Not water resistant and so will wash off quickly.
Natural dye derived from Black walnut husks. Contains juglone, which stunts plant growth.

So instead of me trying many options and finding out the hard way that they don't work, I thought I'd just ask if anyone's done it? I haven't found any similar posts about dyeing soil elsewhere.

 

[just.wing.it]

Could top dress the substrate with fish tank gravel, comes in all colors.

 

[Leo in N E Illinois]

Dyes, if they bond with substrate, tend to be biologically active, bonding to living roots and such to bad effect.

The only "dye" I can think of is an iron supplement, ferrous sulfate, or any of the "liquid iron" plant fertilizer. These will tint your clay a rusty red, if you are lucky and being a natural plant nutrient, won't be toxic in small amounts.

Otherwise the best option is to top dress your potting mix. Take off half a centimeter or so of your clay mix, top dress with an attractive aggregate. Here I can get a purple, gray & brown crushed granite, called cherry stone. Or as Just Wing It suggested, aquarium gravel.

Also, top dressing with moss, living moss, over part or all of the pot is an option. My favorite moss is "crack in the sidewalk moss". I do not know the real species name, but it is ubiquitous and is a nice fine dense moss.

 

[Wires_Guy_wires]

A good dose of humic and fulvic acid will turn it a couple shades darker for a while. Activated charcoal, crushed and then ultra sonicated for an hour will produce a fine black powder.
If it's the top layer only, spray paint and let it dry for a couple days or weeks.

Or grow some algae, those turn my pink cat litter green in a couple weeks.

 

[MrWunderful]

Top layer of gravel, mulch, or sphagnum moss

 

[erich_raudebaugh]

Seaweed extract and humic acid will darken the soil, and it lasts awhile. Not permanent though. I use chelated iron on some trees, just applying the powder to the surface, and it stains everything dark brick red. The moss absorbs the iron and it turns black for a couple months. The nice thing is that using either one will stain white pumice.

 

[sorce]

Moss.

Sorce