Vermiculite & Perlite

[Jon Boy]

Hi,

I want to start using Vermiculite and/or Perlite in my cuttings and seed compost mix, but I'm not sure what the differences are between them and whether I should be using one or the other or both.

Could someone explain their uses for me?

Thanks

Jon Boy

[HarryandNess]

Basically, vermiculite holds moisture but perlite improves drainage.
Ness

[Madahlia]

I chuck in a handful of either or both when I'm mixing up compost and treat them as more or less interchangeable. I like either of them for opening up clumpy or fibrous bought compost but I often use sand as well, depends what I've got available. For cuttings I would use about 50% vermiculite or perlite. I have rooted into 100% perlite before now so it does also hold moisture.

http://www.enjoygardening.com/?p=120

[themes]

perlite is a better medium for drainage IMO. its slightly more expensive but its worth it.

[phil75]

A tip i recently got for a drainage medium, cheaper and better than pearlite i am told, is Tesco's own brand cat litter ......its the one that is advertised as 'low-dust' with a pinky/peach colour on the bag, and the one with the pic on that resembles clay granules (best way i can describe it) ....i am trying it now myself, and seems fine (£2.75 ish a bag for about 10litres)

[themes]

thats a very interesting idea phil if it works. never thought about it, but it sounds like it is worth investigation. Doesn't cat litter absorb moisture though....I was under the impression it did, I am toilet trained now and its been a while since I used the stuff now. Its also hard enough here stopping felines from doing their business on compost and bark mixes This might be the open season invite! I am no expert but open minded and not completely dismissing the idea.

I use perlite in Tufa and this might be an interesting alternative and far more cheaper! so I am very grateful for the tip at the very least I will experiment with this and see how the mixes turn out. Thanks

[Dave Brown]

Perlite holds the water in the rigid honeycombe type structure so is effectively dry and improves drainage. Vermiculite gets soggy and wet, and stays that way for a long while, so is not something I'd add to MP stodge. I am very wary of anything that holds water for long periods, as, as soon as it gets colder most plants prefer to be drier, and you can'tdry vermiculite out easily.

[Madahlia]

Thanks, Dave. Having looked into it a little bit it seems that perlite is generally more suitable for my needs although vermiculite is fine for fast-growing young plants needing lots of moisture early in the season.
I lose things over winter through overwatering, I think, so good drainage in a potting mix is quite important for me.

[phil75]

thats a very interesting idea phil if it works. never thought about it, but it sounds like it is worth investigation. Doesn't cat litter absorb moisture though....I was under the impression it did, I am toilet trained now and its been a while since I used the stuff now. Its also hard enough here stopping felines from doing their business on compost and bark mixes This might be the open season invite! I am no expert but open minded and not completely dismissing the idea.

I use perlite in Tufa and this might be an interesting alternative and far more cheaper! so I am very grateful for the tip at the very least I will experiment with this and see how the mixes turn out. Thanks

i was under the same thinking about cat litter being absorbant - i think some are more than others, like the white crumbly stuff is advertised as 'absorbing' - but this one is a more granular type, a bit like clay balls/granules

The guy at the succulent place i went to did explain it to me, as to why he chooses the cat litter over the perlite, but i have a memory like a fish, so as soon as i started looking at the other succulents i'd forgotten what he said, as i was side-tracked as to what else to buy next time i go i will ask again