I love the look of concrete bowls in the garden but hadn't been able to find any at household sales. I saw some articles about hypertufa and decided to give it a try. The recipe I used was
1 part Portland cement (no stones)
1 part perlite
1 part peat moss
1 part water (approximately)
The perlite and peat add texture and keep the items fairly light weight.

I got a few different shaped plastic items and covered them with plastic wrap. (The recipe says you can also use Pam but I didn't try that.) If you want a smooth surface on the outside then use the inside of the bowl. I did learn that the item must be the height you want so the cement holds itself up. I should have cut the tops and handles off the green bowls.

The urn like item is plastic and I got it for 50 cents at a sale. I used it for a base and just covered it with cement. Remember to put holes in the bottom for drainage.

These bowls are great to add color to my shade garden and can be easily moved to different areas. The bowl for this one was the largest bowl from a cheap plastic set.

I planted a fuscia in the 'urn'.

Impatients in most of the others.

This was a fun, fairly inexpensive item to make that requires no special skills. I had to buy a 90 pound bag of concrete which is way more than I needed but it was still fairly cheap[.

I'd be interested if you've ever tried it to see what you made.
Let me know if you give it a try.