Brown Pellets Used in a Greenhouse ?
By Alanb
Cheshire,
United Kingdom 
Hello, I am currently helping my grandson and his fiancee tidy their garden. There was a huge green house on one side of the garden, which they have sold. I am now helping to clear the plot were the greenhouse was located.
I have come across 4 black pots containing small brown round pellets about the size of a glass marble. I would like to know what they are and what they are used for. Thank you for any comments you can offer.
After a helpful reply from Seaburngirl, I now know what these are. I have attached a photograph below from an internet search.
22 Sep, 2021
Answers
Thank you Eileen. I suspected they may be used for that as I seem to remember seeing them on the trays underneath
plants in some greenhouses in gardens that we have visited.
I’ll probably wash them and see if any local gardener can make use of them.
23 Sep, 2021
I’ve just searched the internet and attached another photo in my original question. Thanks again Eileen.
23 Sep, 2021
that is used in forming a bed to sink pots into. I cant remember their name but they are inert [possibly ceramic/clay]. my work greenhouse staging had them and they help retain moisture around the pot.
22 Sep, 2021