ann, I'm going to assume that the "5/6" near your name in your first post is your zone. Hypertufa can remain outdoors in your zone....if it's potted up with a tree or shrub (I've got sedums in some that stay out all Winter) or you tie a piece of plastic over the top so moisture can't get in and if it's on soil, place a board underneath to break contact with the ground or if it's empty, roll it over so the bottoms facing up and place under a deck or cover with plastic. That's the same way that you would treat a concrete planter. Did you do a search on this forum or look at the FAQ page? 1) whatever you did to the concrete to make it crumble could happen to your hypertufa. I would guess too much dye and too much liquid. 2) strong hypertufa recipe===equal parts portland cement, sand and peat moss. Bash the peat moss around to smooth out the lumps and remove any sticks. I sift mine. 3) if the sides of the mold are smooth and you pack the hypertufa mix tight, the sides should be smooth. 4) I don't add colorant to the mix. I paint or stain or leave natural. 5) The size planter you are making should cure in 24 hours. 6) You'd have to check with your mould manufacturer but the hypertufa can stay outdoors in your zone. 7) You don't want to see perlite granules, then don't use perlite. The only way you won't see perlite or peat moss or vermiculite is not to use them because all of them will show through. You'd have to make the planters out of mortar or get a vibrator to vibrate the molds to bring out the cream and that doesn't always work. 8) It's a planter, why would you want it waterproof? 9) Too much colorant! You did right, coat with vegetable oil. I use the spray cans of oil to coat my molds. Elkski, Concrete will cure 90% in 7 days but it never completely cures. You can plant in week. Most plants aren't that sensitive to the lime and from watering the plant the lime will leach out. I do use a water bath (just water) to leach out the lime because until it's leached out, someone that's sensitive to the lime can get a nasty burn. "the dry powders I got said 1 # to aa bag of cement maximum" Most common bag of cement weights 94 lbs. You do NOT need fibers for these little planters! Billie

Could it be a pot design issue? The least likely design to have freezing problems is one that is smaller at the bottom than the top, with outward-sloping sides. When the contents freezes, it tends to expand upward and outward, following the design of the pot. The most likely one to break is the one that is built like a cauldron, with a smaller bottom widening outward in the middle, then shrinking down again toward the top. The freezing contents become trapped and expand beyond what the pot shape can tolerate. The other problem is tufa itself. Organic materials rot away (peat, coir, sawdust, etc), leaving channels that water can move through and into. Some of it gets trapped when a freeze hits, and all those little bits of swelling ice weaken the tufa overall. A little bump the next year, and here you've got several pieces of one pot. If you've got a pot you're really proud of, plant into a removable cache pot, and put the tufa pot in the garage or shed for winter, after drying it out as well as possible. You can fight the laws of physics all you want, but you will lose. Just plain water carves canyons, rain wears down mountains, and tiny little bits of ice breaks pots. It's the Law. Sue

Thanks, Billie I didn't cover it for the first night. I didn't want the piece to get the same texture as the bag. The next morning I covered it up first thing. As for the bird baths and the like, when knocking on them, I think the peat moss gives them a more muffled sound. This is why I thought it wasn't made of concrete (straight mortar). I'm feeling pretty confident about what my next piece will be. As for the manhandling, my next piece will require me to flip it over at some point, before it's too late to carve. So far, both of my molds have been outter molds. I've noticed that the rim, which is up against the plastic, which in turn is up against the floor, always has a plastic glue-like finish. I want to make sure I can manipulate this before the tufa is dry, and that will require flipping over. Also, I am going for a rock-like look, which means thicker walls, which means heavier piece, which means, handling it will require precise timing. You'd think I'm crazy going for something more difficult when this simple thing failed, but I think I learned some valuable lessons here. I'm going to start creating the mold. One of the lessons I learned, is you can make a mold out of anything. This new approach is going to be really interesting and I am surely going to post it here, hopefully with successful results this time :-) As for working outside, now is a good time here in FL, because it's not raining, although I did have a stroke of bad luck the next day, because it did rain. Luckily, my tufa had been covered by then ;-)

Well, being that I'm in zone 8, I'm still sowing seeds! Does 're-potting' count? In that case, because the usually rather dry September & October has turned into heavy downpours.... I potted up the newer 'Hidcote' Lavender, in lean well drained pot. Hoping it is as intense violet as one I had in the past which drowned/rotted in the typical ground up pine bark, that most perennials seem to be sold in, these days. I'm figuring out, that must be what kills off my Oriental Poppiy cultivars & by the time they ship them, it seems late & they don't like being transplanred bareroot, nor peat mix when potted & don't like disturbance after leafing out. So that's always a problem. Besides, I'm just finishing uo, with mail ordering! I'm almost ready to plant some Scabiosa caucasica 'Fama Deep Blue' sown about a month ago & some 'bearded' Dianthus thay has some extra long fringed petals, even more so than 'Spooky'. Seems fortunate that I got some free seeds, from a nearby local planting, as I can't locate a source- just a few photos on the 'net! I bought some 'Coral Reef' Oriental Poppies from High Country Gardens & hope they are as pink as shown in the catalog. Bluestone, has gone to single coco peat & no longer offers three packs AFAIK & besides, when it did finally bloom, it was half pale orange & they explained it away, as "that's why they call it coral"- huh? I said pink coral is just that- pink! But they replaced it with an Eryngium, that didn't seem to be the 'Sapphire Blue' that others seemed to grow... But maybe the Eryngium alpinum roots I ordered will be more satisfactory, next year. Thompson & Morgan , since being overtaken & bought out, still doesn't have seeds in stock, of the one I really want; 'Blue Lace'. Meanwhile, Van Bourgondiens moved out of State & sold off & at least I don't have to pay sales tax anymore, but maybe I'll wait until next month for something from there. I'd have planted some New Zealand hybrid Delphiniums by now, but the price per plant, really gets to me & I sowed seeds from Jung anyway. Maybe spring is better for ordering & planting potted ones... I do have Fiona Coghill Daisy on the way, so that will go in the ground upon arrival, as will Hot Papaya' coneflower & a newer(?) phlox 'Tiara' that's a double white. 'Blue Paradise' & 'Nicky/Dusterlohe' would have been bought but I need to move them from the previous residence & are fabulous in flower. I don't know if Dicentra ' Burning Heart'(?) made it through the summer, but I'll have to see about that, later. I'm going to plant Peony 'Duchess de Nemours, as soon as it arives. I've a tree type(suffruticosa) 'Hanakisoi, that definitely needs planting. I'm surprised it stayed in leaf, this long. Well, I've still got Colorado Columbines I need to sow, for transplanting when it gets cold, cold. The McKanas just came up & aren't ready yet. Snapdragons are perennial here & I go for the All American Selection tall ones ( forgot the cv. name, but Park seed has them... & try sowing some Tetra mix tomorrow, which are tall also. Just got around to sowing the, Forget-me-nots in with Angelique Tulips (#1 Planted!),'Excelsior' or 'Shirley' Foxgloves & 'Cup & Saucer' Canterbury Bells, even if they aren't really perennials. Not sure what to mix with 'Blue Parrot' Tulips (#2 planted!), as they're actually more deep lilac. Any suggestions? Maybe I should have interplanted using the Papaver alpinum, from Ed Hume seeds... I have no idea what to coordinate with the Sweet Sultan, (Bavicchi seeds, from Italian Tool website.) Maybe the Lavandula 'Hidcote Superior', though if I'd bought yellow Centaurea moschata 'Dairy Maid' instead. Darn it... Well, the Moon flower (Ipomea) just grew roots through the bottom of the pot & don't want to disturb it, just to plant it. Do the roots get stored? I dunno, do they just get planted dormant & sorta comeback, like Jalapa 'Four O'clocks',maybe? If I could locate some Anchusa 'Loddon Royalist' I'd plant that, as regular azurea species gets so tall. Most people are planting Pansies around here & so I'm behind, as I sowed 'Chalon Supreme' & some 'Pettycoat'. I could have covered the dormant Anchusa, with these. I guess I could plant (finally, here it is, #3!) 'Nelly Moser' Clematis I got on sale for 3 or $4 from Lowe's, tomorrow, but I've also got to put in an old 'Harry Lauders' Wlaking stick or Corylus contorta, that someone discarded, simply because it had suckered after some years. Why not save about $40. on a free one. Could you resist it? lol Happy growing to all.