Joanie

They sell "decorative lava rock" in small bags in most nurseries. Try Home Depot or Lowes or your local equivalent. Look in the area where they have smaller bags of cactus mix, etc. They usually have pumice too. Think about the places that would have cactus displays, etc. They have the right size for what you want.

Pea gravel is just a space filler, it doesn't do a lot of good. I repotted some trees that had been put into a lot of pea gravel and boy were their roots awful! Same with decomposed granite, and it makes the danged pot so heavy! Pumice or lava is much better. Pumice or lava are like Thomas's English Muffins, they are good because of the 'nooks and crannies'.

Perlite is like crispy popcorn, it comes in big particles but lots of small stuff and dust too. It's great for cuttings particularly. It's also cheap enough to use for lightening up growing beds, or as a part of the mix in big growing boxes. A really big bag... maybe four feet tall and a foot or so in diameter... can be had for about $17. It lightens the soil and keeps some moisture in, and really encourages good root growth.

Keep the bark percentage low, because it can take nitrogen away from the roots when it starts to decompose.

Joanie

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