Hey, Christine

Let's see if I can address your concerns one by one.

> I'm no way ready to start, and from what I read, I have to wait for better weather

If your project is too big to carry out, you will have to do it on location. Then, yes, you have to wait for right weather. If you have an area indoors, where temperatures are moderate, you can work there. I work in my garage.

> Using one of the many, similar hypertufa recipes, and using appropriate space-suit attire, I will make my mixture.

You just need rubber gloves. The lime will roughen your skin. I work in shorts and old shoes. I use clothing I don't want to be seen in, something I wont mind throwing away once I've taken it too far ;-)

> I'll have to build some kind of support structure in the trough shape I want.

I've discovered just about anything works

see Why Square?

> I think I'll have to use a nonsticky thing so the hypertufa doesn't adhere to my structure, if it ends up being plywood

As you can see in the aforementioned link, dressing with garbage bags works quite nicely.

> I think, for the inside mold, I could probably use appropriatly shaped cardboard boxes. Updside down seems the strongest

Remember cardboard should get wet or it will crumble. You can dress it in plastic bags to prevent this, or try something else. As long as it withstands the weight of a couple of inches of tufa, anything works ;-)

> I'd have to make this in place and cure it for a heck of a long time.

If you can't carry it, and you can't roll it using a trolly or something to that effect. I put mine in position after curing for a week, but I'm in zone 10, where temperatures are more cooperative.

> I am enamoured with Dena's leaves. They're absolutely gorgeous. Would it be possible to create some leaves to decorate these containers?

Look up "double lead fountain" in this forum. I'd give you the link, but the admins where I work block everything. I'll get it to you when I'm back home if you haven't found it yet.

I would do the leaves first. Then, when they're dry, start working on the plantes and slap the leaves on the outter part while the tufa is still wet. All depends on the effect you're looking for.

Hope this helps

Oh, and I musn't forget: CONFIDENCE! Worse case scenario, a couple of projects won't work (this happened with me). If you're concerned, start with small projects, like building small planters using small molds, like yogurt containers or something. It really isn't rocket science :-)

For dressing up your planters, try this link:
http://www.cpag.net/guide/4/4_pages/4_3.htm

There is more knowledge and inspiration than I can stand!

Good luck!!!

Rubber gloves *and* a dust-mask or respirator. You only have to wear the mask until the cement & sand (if you use sand) are wetted. Silicosis rivals asbestosis in future nastiness.

Double gloves are good if you use fragile ones.