Water retaining gel for pots - Free!!

If you are using Covid lateral flow tests, they come with small packets of desiccant which is water absorbing, but also water retaining and pretty much the same stuff as you'd buy to keep pots moist.
So save the little packets and mix the contents with your potting compost. You won't save a fortune, but as they say up here - 'mony a mickle maks a muckle.' and its better than throwing them in the bin.

 

Silica gel.

 

Yes, the same stuff as may be found in disposable nappies

 

Yes, come across some of those in various places.

 

I wished some one had told me you shouldn't use used ones!

 

That's the 2-in-1 version, with fertiliser.

I'm not too sure how efficient the silica gel is, but the gel crystals in nappies certainly do work. It's basically the same stuff that is sold as water crystals, they absorb a lot of moisture and swell up to gelly blobs.

Then again, silica gel feels like it could also work as grit in the compost.

Interesting idea, worth some experimenting

 

Just done an experiment and the silica gel doesn't seem to be swelling like the water storing crystals or the stuff in nappies.
Its just stayed hard and gritty.

 

What a dedication Pete

Yes, if I remember my days in a lab, the stuff captures moisture thanks to it's porous structure rather than absorbs it. In the lab it's heated up to evaporate any moisture, then quickly poured into a desiccator, and the stuff to be dried is placed on top, and the lid is sealed tightly.

However, silica might work very well in potting compost to add porous, gritty inert material in. Never thought of that, and the little pouches come with anything you buy so win win.