Vermiculite Vs Perlite

gflynn · April 23, 2006

Up to now I have only used vermiculite in a 50/50 mixture with peat moss for container soil. vermicutite seems to absorb water and hold it and not break down over the years. These are nice qualities.

Is perlite equvalent or is it different?

Greg

cthomato · April 24, 2006

I mix both vermiculite and perlite in my potting soil. I thought perlite did a better job at water absorption than vermiculite. And I thought vermiculite does a better job keeping the mixture friable than perlite.

I'm trying Zebra water absorption pellets this year instead of perlite in some of my containers.

Chris

gflynn · April 27, 2006

ctomato,

Nice bunnys. Also, I think I will mix the two together and see what happens.

Greg

**Mischka** · April 27, 2006

Vermiculite is a mineral; mica, to be exact. When heated, it puffs up, and in this state it absorbs and holds water. However, due to its tendency to compact, it shouldn't make up more than 25 percent of a potting mix.

Perlite is a white volcanic substance that is a derivative of silica. It too is heated so that it puffs up. Yet, perlite does not readily absorb water, making this the main difference between it and vermiculite.

Vermiculite is used primarily in potting mixes (because of its water-holding capacity) and perlite for rooting cuttings. However, because perlite is sterile, the cuttings must be replanted in a potting mix that contains nutrients. Do this once roots begin to form.

You can use both perlite and vermiculite interchangeably. Because perlite and vermiculite are roughly one-tenth the weight of sand, they are ideal additions to potting mixes for folks who garden on terraces or rooftops where weight is an important consideration.

cthomato · April 28, 2006

Thanks for info! Boy did I have it backwards!

travis · June 25, 2006

Vermiculite is expanded mica.

Mica schist are metamorphic sedimentary rocks ... usually changed by compression and heat from shale. As such, the shiny mica layers are sometimes interspersed with other sedimentary stuff like talc, asbestos, etc. Sometimes the layers between the shiny mica are feldspar. Depends on the mine source.

Talc sometimes has asbestos in it too. Some sources of talcum powder used to have asbestos in it. Some sources of vermiculite did too. The danger is in the breathing in of the asbestos, not necessarily in eating it. However, I would hope the responsible regulatory agencies have eliminated asbestos from commercially available talcum powder and vermiculite.

PV

gflynn · July 3, 2006

BIG UPDATE!

So this year I tried my potting mix with either Peat moss and Vermiculite or Peat moss and Perlite. The results are very interesting!

The two tomato plants with soil that contains vermiculte look great but the other two plants with the soil the contains perlite have significant leaf curl. This four plants are next to each other in my driveway. I also used the half perlite mix with my peppers and they are having leaf curl issues as well. I have never even seen a pepper with leaf curl until now.

Anyway I will never do that again. Instead I am potting up another plant now and I am going to try 50% peat moss 30% vermiculite and 20% perlite. We will see how well this mix works.

Now I am not sure that my conclusions are correct but perhaps some of you folk also have some experience with this that you could share?

Greg

timcunningham · July 3, 2006

You could be opening a can of worms here.

I know that some here (me) believe in the power of vermiculite, while others have stated here uniquivocally that perlite is better for tomatoes.

This is a universal question, that has divided people for ages. It is more contentious than: John Lennon vs Paul McCartney, Boxers Vs Brief, or Paper vs Biodegradable Plastic. The answer to all probably says more about the chooser than choosen.

That being said: I stand wholeheartly with the persecuted vermiculite - be he ever so loamy. I know these action could get me banned for not being so light and breezy, but this is the strength of my faith and conviction!!!!!!

P.S. My tongue is planted fimly in my cheek. Did you notice?

Bryan24 · July 9, 2006

Bryan's used both. I think he used vermiculite in the pots for water retention. And I think he put pearlite in the beds to make the soil light and fluffy (clay based soil sucks). It really worked in the beds, the plants have MUCH larger root systems this year.

laurel-tx

gflynn · July 12, 2006

Good to hear bryan,

I have supposed the same thing and I have lots of clay soil.

Greg

April 23, 2006	#1
gflynn MAGTAG™ Join Date: Feb 2006 Location: Gaithersburg, MD Posts: 437	Vermiculite Vs Perlite Up to now I have only used vermiculite in a 50/50 mixture with peat moss for container soil. vermicutite seems to absorb water and hold it and not break down over the years. These are nice qualities. Is perlite equvalent or is it different? Greg

April 27, 2006	#4
Mischka Tomatoville® Administrator Join Date: Jan 2006 Location: The Bay State Posts: 3,207	Vermiculite is a mineral; mica, to be exact. When heated, it puffs up, and in this state it absorbs and holds water. However, due to its tendency to compact, it shouldn't make up more than 25 percent of a potting mix. Perlite is a white volcanic substance that is a derivative of silica. It too is heated so that it puffs up. Yet, perlite does not readily absorb water, making this the main difference between it and vermiculite. Vermiculite is used primarily in potting mixes (because of its water-holding capacity) and perlite for rooting cuttings. However, because perlite is sterile, the cuttings must be replanted in a potting mix that contains nutrients. Do this once roots begin to form. You can use both perlite and vermiculite interchangeably. Because perlite and vermiculite are roughly one-tenth the weight of sand, they are ideal additions to potting mixes for folks who garden on terraces or rooftops where weight is an important consideration. __________________ Mischka One last word of farewell, Dear Master and Mistress. Whenever you visit my grave, say to yourselves with regret but also with happiness in your hearts at the remembrance of my long happy life with you: "Here lies one who loved us and whom we loved." No matter how deep my sleep I shall hear you, and not all the power of death can keep my spirit from wagging a grateful tail.

July 3, 2006	#8
timcunningham Tomatovillian™ Join Date: Feb 2006 Location: Middle Georgia Posts: 241	You could be opening a can of worms here. I know that some here (me) believe in the power of vermiculite, while others have stated here uniquivocally that perlite is better for tomatoes. This is a universal question, that has divided people for ages. It is more contentious than: John Lennon vs Paul McCartney, Boxers Vs Brief, or Paper vs Biodegradable Plastic. The answer to all probably says more about the chooser than choosen. That being said: I stand wholeheartly with the persecuted vermiculite - be he ever so loamy. I know these action could get me banned for not being so light and breezy, but this is the strength of my faith and conviction!!!!!! P.S. My tongue is planted fimly in my cheek. Did you notice? __________________ Visit my site: tomatoindex.com a database of over 2700 varieties. Vote for your favorite.

April 24, 2006	#2
cthomato Tomatovillian™ Join Date: Feb 2006 Location: SoCal z10 Posts: 96	I mix both vermiculite and perlite in my potting soil. I thought perlite did a better job at water absorption than vermiculite. And I thought vermiculite does a better job keeping the mixture friable than perlite. I'm trying Zebra water absorption pellets this year instead of perlite in some of my containers. Chris

April 28, 2006	#5
cthomato Tomatovillian™ Join Date: Feb 2006 Location: SoCal z10 Posts: 96	Thanks for info! Boy did I have it backwards!

June 25, 2006	#6
travis Tomatovillian™ Join Date: Jan 2006 Location: Evansville, IN Posts: 2,984	Vermiculite is expanded mica. Mica schist are metamorphic sedimentary rocks ... usually changed by compression and heat from shale. As such, the shiny mica layers are sometimes interspersed with other sedimentary stuff like talc, asbestos, etc. Sometimes the layers between the shiny mica are feldspar. Depends on the mine source. Talc sometimes has asbestos in it too. Some sources of talcum powder used to have asbestos in it. Some sources of vermiculite did too. The danger is in the breathing in of the asbestos, not necessarily in eating it. However, I would hope the responsible regulatory agencies have eliminated asbestos from commercially available talcum powder and vermiculite. PV

July 9, 2006	#9
Bryan24 Tomatovillian™ Join Date: Jul 2006 Location: San Antonio, TX Posts: 176	Bryan's used both. I think he used vermiculite in the pots for water retention. And I think he put pearlite in the beds to make the soil light and fluffy (clay based soil sucks). It really worked in the beds, the plants have MUCH larger root systems this year. laurel-tx

July 12, 2006	#10
gflynn MAGTAG™ Join Date: Feb 2006 Location: Gaithersburg, MD Posts: 437	Good to hear bryan, I have supposed the same thing and I have lots of clay soil. Greg