On April 16, Steven Chamblee introduced us to ancient stone troughs of England. During the class we created lightweight faux stone troughs by blending mortar, peat moss, and perlite. We learned the secrets to making custom shapes, deep texture, and that age-old look that looks great in any garden.
Enjoy these notes from the class:
1 part perlite
1 part milled sphagnum peat moss (powdered, NOT the stringy kind)
1 part Portland cement (preferably NOT the white kind)
1 part water
Binding fibers (commercial “fiber mesh” or fishing line cut into 8” pieces)
You will also need:
Mixing vessel (I prefer a wheelbarrow)
Mixing tool (I like a garden hoe)
Scoop (to move mix from mixing vessel to mold)
Safety glasses (which …ahem… never work if you don’t wear them!)
Dust mask (which…ahem…ditto)
Mold (sturdy cardboard box that nests inside larger box w/1’-2” air space on each side)
If you want to embed items into the surface of the trough, hot glue them onto
the interior of larger box—this is easier if you open it up and lay it flat, then
refold and secure with duct tape.
MIX IT UP!
(Slow movements will reduce the dust factor.) Gently place perlite, peat moss, and concrete (in that order) into mixing vessel and gently stir a few turns while dry. Add half the water, toss in the fibers and begin mixing, gradually adding additional water until the mix is thoroughly blended (check the corners). Finished mix should be the consistency of cottage cheese. If too soupy, add small amounts of cement until “cottage cheesy.” Place a 2” layer of mix into the bottom of the larger box. Place smaller box inside and center it within. Carefully add mix a little at a time down into the side spaces—do this at the corners first, so the mix doesn’t shove the small box out of position. Fill to desired height. Pat sides of box and/or slide a paint stirrer up & down through the mix to settle it. Let set for an absolute minimum of 24 hours—preferably 72 hours—before removing the form boxes. (Just rip them off!)
Create great texture on the surface of your trough by hitting it repeatedly with the claw end of a claw hammer (for Pete’s sake, use an inexpensive one). Proceed gently at first until you get the hang of it. I do NOT recommend using a chisel because it directs the force of the hammer blow too deeply, which can crack your trough. Remember to wear safety glasses —they don’t do any good if you put them on AFTER you have a chunk of funk stuck in your eye! You can also carve simple shapes and textures into the trough surface with a grinder equipped with a masonry blade. Make sure to use a pattern or template if you are attempting precise shapes. Great fun, but it is VERY dusty, even with a water trickle on the surface. Also, grinders are not for the timid, and should not be used by folks who are not physically robust – you can get hurt if you mishandle a grinder.
Unless you are using your trough as a birdbath, water fountain, or aquatic plant pot, make sure to drill drainage holes in the bottom of it. Make sure to use a masonry bit— 1/3”– 1/2“ diameter ought to do it. I recommend several holes
for good drainage. Also, forget about that old myth of gravel in the bottom of the pot to improve drainage—it just ain’t so. If you are worried about the potting soil falling out the drain holes, just use a coffee filter to cover them before adding soil to the pot.
It’s your trough, so plant it the way you want, but I recommend starting with succulents. They’re tough and look great in troughs. Always use a quality potting soil! (If it’s cheap; it’s not good.) Don’t forget the old “thriller/filler/spiller” guideline — it works pretty well. Also, vary color and textures. Have some fun and don’t be afraid to change your mind. If it turns out super cool, send me a photo!
Peace & Love,
Steven Chamblee is the Chief Horticulturist for Chandor Gardens in Weatherford. He serves as Consulting Editor and Author for Neil Sperry’s GARDENS magazine, and writes a monthly e-newsletter column entitle Native Son, and is an Adjunct Instructor for Tarrant County College and Texas Christian University’s Extended Education. He has studied public and private gardens in England, Denmark, Canada, Costa Rica, Mexico, Hawaii, and across the continental United United States. He is proud to be one of those rare horticulturists who concurrently talks the talk and walks the walk.