Small Fun With Fake Stone

Diamond rings, gold watches and the keys to a new Porsche – all good things in small packages.  While I don’t have much experience with any of those, I am crazy about tiny plants in special pots, a unique branch of horticulture known as trough gardening.

Who invented the trough garden?  The answer may be lost in time.  Perhaps someone with a green thumb had a stack of obsolete stone animal watering troughs lying around, as well as a few stone sinks, and decided to plant something in them.  Or, maybe a plant collector with tiny alpine plants, succulents and other wee treasures found they looked good and grew well in troughs.  Like peanut butter and chocolate, a great combination was born.

Then the laws of supply and demand kicked in.   Old stone sinks and troughs are rare antiques, and the few available command big prices.  Luckily, some genius came up with a substitute version, which could be made by hand using a mixture of cement, peat moss, and sand.  These troughs became known as ‘hypertufas,” since they resembled lightweight, somewhat porous tufa stone.  Today, all sorts of variations on the faux stone trough garden exist, most far exceeding the average rock.

I’ve been making hypertufas for years and have a modest collection of a dozen or so planted with unusual sedums, sempervivems (think hens-and-chicks) and other small plants.  While real stone troughs can be several feet long and hundreds of pounds heavy, hypertufas can be much smaller – mine have been made using plastic dishpans or storage bins as molds and weigh less than 20 lbs.  They stay outside all year, so the diminutive plants inside must be cold, heat and drought tolerant.

If you have at least one small creative bone in your body, you can make a hypertufa trough.  Here is a rough outline of the process – look for details on the web.  Find a moderate-sized plastic storage bin of attractive shape that is somewhat flexible.  In a large bucket or wheelbarrow, thoroughly mix one part Portland cement, one part sand and one part peat moss.  Add water, a little a time, to these ingredients and keep mixing until the product has the consistency of very stiff oatmeal.  Remember that the stiffer cement is when mixed, the harder it will become as it cures.

Next, cover the bottom of your storage bin with one inch of the hypertufa mix.  Pack it down tight.  Then form the sides, working up evenly all around, until you have something that looks like a planter.  Carve a drainage hole in the bottom.  Cover the new-born trough with a plastic bag and place in a cool location, occasionally spraying it very lightly with water, for one week.  Then pop it out of the plastic bin, and use a screwdriver or wire brush to scratch up the surface, making it look more stone-like.  Let the trough cure out in the sun and rain for a few weeks before planting.

You’ll have fun planting your diamond-in-the-rough with real jewels:  mini plants.