I have seen a recipe that could be used. It speaks of Australian supermarkets but is easy to replace that for a supermarket in your local country

"Starting seeds the traditional way usually includes a seed starting mix made up of equal parts of peat moss, vermiculite, and perlite. When mixed together with a little water, this mixture will hopefully support the growth of your new seeds. The risks are too much water, too little water and even seed rot if the soil is too wet. And this happens just as much to experienced gardeners at times! Here is how you can start to germinate seeds in a new and maybe more efficient manner!

Gelatin is the perfect medium to grow seeds, especially those difficult to start seedlings. Gelatin is made from animal bone and therefore has high level of nitrogen and other minerals. Add to that the sugar from the gelatin mix and water and you have a perfect place to grow those little seeds! I just looked at Coles online and you can buy the container of gelatine in the picture for $3.75 for 100 grams.

You will need:

Gelatin mix ( used to set jams etc, buy at Woolies or Coles)

Water sterilised containers such as baby food jars or small glass containers, boil water, cover jars in water, allow to cool in the water. Handle with plastic gloves or washed hands from then on.

Water sterilised toothpicks or tweezers.

Sheet of clear plastic , ziplock bag or piece of glass

Powdered cinnamon.

Prepare your gelatin per package instructions. Pour at least 6cm of liquid gelatin into your sterilised containers. Once the gelatin mix has cooled, push at least 3 seeds into the gelatin of each gelatin filled container using a toothpick or pair of tweezers at a depth of no more than three times the width of your seed. Place your containers in a warm, sunny spot and cover with clear plastic, ziplock bag or glass.

No need to water or feed! Be mindful of mould forming. If you see mould, just dust with a little powdered cinnamon to keep it in check.

Once your seedlings have sprouted and are about an inch or two tall, transplant them (with the gelatin) by wedging them out with a pop stick or teaspoon into the seed starting mix that is described above. The gelatin will continue to "feed" your seeds as they grow and you have less risk of injuring your new seedlings. Wash and sterilise your jars again removing all old gelatine and start again!"

Thanks Jacob Simons !

It's going to be for a longer growth period, as I intend to use some slow-growing plants to see the root development over a longer period of time with the kids, but adding some gelatin might indeed be beneficial for the nutrients; I had not thought about it! Thanks for the idea!

Thanks Abdel Rahman Mohammad Al Tawaha

You could also use water crystals, tiny balls that swell up to the size of small marbles. I've seen cuttings rooted in a glass with these. Or you could use a combination.

The simple procedure is to germinate seeds in a petri dish lined with moist filter paper, and to water 1-2 times till the seedlings are big.

why not use Phytagel?

Thanks S. Wenkart ! I was looking more for a synthetic media to help with contamination, and since I was trying to avoid proprietary blends for budget reasons, I kinda glossed over Phytagel. With your suggestion I went back to read more about it: it seems it is a gellan gum. That, I have access to.

And by now, I have gone from looking for the ideal solution to simply finding a doable one, so I'll be happy to try this :)

Thank you!

Srinath Rao, thank you for your suggestion. It would be simple to do it this way, but root formation is what we'll be looking at, and a clear plant growth media is better at that ;)

But thank you for your input :)

Added picture of roots in gelrite

S. Wenkart . Nice! Thanks :)

Dear, Dr. Vines

You can maintain aseptic conditions in this method too.

Try with Agar 0.5% gel and a phosphate buffer pH 7.2.