
Growing your cacti and Succulents in non organic substrate such as Pumice.

I first started experimenting with pumice in 2017 with two Christmas cacti and the experiment worked well and had two lovely flowering plants for two years before giving them away.
However, the majority of my cacti and Succulents were grown in the traditional John Innes substrate that so many growers use. Over the years, I found the quality of John Innes had become poorer with more and more bags containing stones, twigs, and even live roots, so 2 1/2 years ago, I started growing my succulents cuttings, small Lithops seedlings and tiny or small Conophytum in 1-3 mm pumice and for larger plants 2 to 5 mm or a mix.
Faucaria from seed to seedlings in 1-3 mm pumice.

If you plan to have 3 or 4 plants in a pot, spray the surface which enables you to make a planting hole for the roots. After a couple of days, reseating may be necessary as the pumice moves slightly each time you bore a hole for planting.
While more expensive than John Innes and other traditional substrates, pumice is 100% reusable and comes into its own at times of repotting. If repotting with already used pumice, just rinse it and let it dry. If a plant has been mushy or died in the pumice, again rinse it and microwave it for 3 or 4 minutes.
Pumice being a volcanic rock has very little feeding – if any – and so I feed mine with Maxicrop, a Seaweed Plant Stimulant – a natural feeder – at 1/4 strength on a monthly basis during the plants growing seasons only. Being a natural feeder, should you slightly overfeed the plant it shouldn’t come to any harm. You can use other feeders such as Chempak but please check with the manufacturer about overfeeding.
This year I have had my best Conophytum season with over 40 of them flowering in 3 months.

Should readers be interested in experimenting with good quality pumice, please PM me as some suppliers charge ridiculous prices for some poorer quality pumice.
Repotting
When transferring from organic substrates it is important to wash as much of the substrate out of the cacti or succulents roots before repotting.
Pumice is also good for producing strong healthy roots as the Faucaria below shows.

This Faucaria doubled its roots in 7 months after being transferred to pumice.
Having completed my transfer to Pumice, I have not had any mealy bugs for 2 years.
I also purchased Provanto Ultimate Bug Killer concentrate which you spray on your Cacti, Mesembs and Succulents up to 5 times a year. This greatly helps to kill or dissuade several bugs from attacking the plants.
