Since i did mine with vermiculite instead not sure about the perlite part. (i wanted the fawn color & sparkle it adds and don't care for the perlite look). I can tell you that there's a forum on here i'd definitely do some reading on- esp their FAQ, and there are lots of great articles there. One thing that i didn't see mentioned that much when i was looking at first is to try to do it right about now- when the weather's above freezing, but still below about 85 degrees. Above 90 and the cement doesn't set up right. Be super duper careful when you unmold- the tufa is very fragile for a surprisingly long time. Mine didn't harden fully for about 2 mos- but that may partly be b/c i did them in the heat of summer. They are quite strong now.

There's some interesting freeform tufas on one or 2 pages of sedum.net, too- they are more of the style i made mine in. They go step by step through the process.

Before you do a whole trough, i'd start with a small container and learn the feel of the tufa and how it handles, dries, etc. You probably will make mistakes- too wet, too dry, unmolded too soon or late, ect, and that way you won't have committed too much time, money & effort until you get the kinks worked out. It isn't hard- you just have to have a feel for the material. Whatever you do, have fun!

Check with your local gardening center or nursery. That's where I found mine. It will last a l-o-n-g time. :)

Thanks guys. I will follow your advice. First batch is going to be 2 smallish troughs to see how they turn out. I found out that Logan's sells the vermiculite in bag bags so I'll try a batch with each of perlite and vermiculite and see how it goes.

Some of the forums mention adding a little sand for strength. Any of you care to share your formula/recipe?

RJ

def add sand, and it doesn't take much. By the end of the run of troughs i made, i was mixing about 3 parts sifted peat; 2 1/2 parts vermiculite; 1/2 part sand; 3 parts cement. It's easy if you use cool whip containers or some such- i found that was about the right amount for me to mix thoroughly & be able to work before it got too anything, and it was the right amount i could carry, too. I mixed in a plastic trough set inside a wheelbarrow. Mix them all by hand together dry, then begin to add your water. I also found it was sooo much easier to use a hose set on mist to add the water. You can wet the top surface to begin with, then have one hand using the hose, while the other mixes with a tool or just with your hand(in heavy gloves, of course) till it's about 1/2 way wet, mix some more, then just add a few squirts at a time of the water on mist- it goes from stiff batter to a slurry really really fast. Like literally seconds. Be sure you have on a mask and eye protection, too.

forgot to say that hudson's hardware in garner carries the vermiculite in big 5 cu ft bags (i think that was the size- about 3.5'x2') for about $20 if i recall right. That bag was enough for me to do 5 medium sized troughs, and i think i went through about 1.25 bags of portland at the same time. and about 1/3 a bale of peat. You do need to make sure you're working with portland cement, not premixed concrete.

Also, there's a scad of recipes to try in the FAQ of the hypertufa forum.