Sounds like that beer will taste pretty good. I know when I first started I had many failures. In fact, I took a year off from it and started again. I've always found that if I made up a batch and just make it like cookie dough instead of cake batter, you can form it around anything. You're right, if it's too soupy, you just can't handle it. My favorite recipe is two parts of peat moss and perlite to one part of portland cement. I started my hypertufa adventure with adding one part more of portland cement, but I prefer the lighter mixture. If I want the projects to hold water, I just get a waterproofer for concrete projects. A gallon goes a long way. Good luck and have patience. I've made hundreds of projects and each has its own story.

Well I checked last night as was surprised by how shinny and hard the surface had became in just 8 hours. It was very hard. I worried that it would be unworkable in the morning.. But it came out of the cooler mold and despite the small cavity inside due to slumping everything will be fine. This will only hold 1-2 small plants. This had a white plastic bag that did provide creases but also was hard to dig out most of it.. I did find one of those new fancy plastic abrasive wire wheel brushes for the drill motor worked great to take the sheen off and expose the air pockets.. And mine was one of the lighter grits they make.. I will be buying a more aggressive one for next time.
The other one was inside of a an Oatley plumbers black box I forgot the pam so I had to rip it off (3$). THis form worked great and has a nice lip on it. to bad it is square and not the golden rectangle
I also couldn't use the dowel drain holes and so I used a cheap cement drill to put drain holes in. Soaked in water and bagged then and put in the garage to age and protect from frost.

Now I need to learn how to de alkaline them so I can plant in them in the next 3-4 weeks??t

oh by the way I used the formula
2 pts portland
1 pt sand
5 pts perlite
some fibers
forgot the admix
didn't premix the dry stuff first
I thought this heavy perlite would show more at the surface than they do???

elkski,
"By the way I have mixed up scores of bags of cement/spec mix for fence posts and rock work. In fact I have rocked 10 tons on my block walls and did a fireplace this last winter." Doesn't matter about mixing concrete or mortar because you work with those mixes much wetter than hypertufa.
Regarding the perlite, I'm surprised that you're not seeing a ton of perlite at the surface given the amount that you used.
Windy day or not, safety glasses are your best bet until all the dry ingreidients are wetted. You are wearing a safety mask so you're not breathing in all the dust, right?
If you unmold in 24 hours for something this small you only need a hand wire brush and it's cheaper (dollar store) than a wire wheel.
What temperate zone are you in? You mention frost.
To leach out the lime, when the weather improves you can put you planter in a plastic tub (muck bucket-5 gallons) works well. Change the water every day for 3 days and most of the lime will be leached out. Wear rubber gloves if you have to put your hand in the water because the lime-water can burn your skin. When warm weather is in my area I can make a planter on one weekend and plant it the next weekend. Billie

It was really hard and not near as easy as what I thought.
#1 pot was in a 3" thick Styrofoam medical supply cooler and was very warm when I took it out this am. #2 pot was in the ground to help support the sides of the plastic mold.
I was also surprised at how little perlite shows. My perlite was very fine lots of dust and the largest spec was maybe 1/8" dia .. is this normal size??
Had a good respirator on most of the time. but the wind was so swirly that even goggles would have let the dust in my eyes. I made another one today and mixed it real dry. But it still slumped.. I will make it even dryer next time and might have to pack it in... I should be out there cleaning it up but its cold today.

I should mention that I had less cat fur balls in yesterday batch by putting the fibers in the drymix and using a drill mixer compared to adding to the water/admix today. I might have mixed it up a little to much and all the fibers kinda came to the top in the head that formed due to the admix. Just FYI.. mix slower..