Stone troughs provide a beautiful setting to display alpines. There are many other means of displaying them (see our guide to growing alpines in containers <link>), but many enthusiasts agree that a stone trough is hard to beat.
Stone can be an expensive material, however. A simple alternative is to make a trough that looks like stone. It’s not as hard as you may think! This guide will show you how to make a mix called ‘hypertufa’ and how you can use it to make stone-like containers.
Tufa is a porous natural limestone rock. Over 90 years ago, it was discovered that alpine plants grew very well on it (as you can see in the images above).
Hypertufa cement-based substitute that you can make yourself. It can be used to make simulated stone sinks or even to custom-make your own rocks!
Depending on the finish you desire, there are various recipes you can follow:
|1 part sand
1 part cement
1 part bark
|5 parts sand
2 parts cement
3 parts bark
|1 part sand
1 part cement
2 parts bark
TIP: The tufa recipe creates a very porous product that is vulnerable to frost. If you live in a very cold area, toughen it up by slightly reducing the volume of bark.
You can usually mix the materials straight from the bag. If the sand is very wet though, allow it to dry out first.
Mixing can be a messy process! If you’re making several batches, we’d recommend buying a Spot Board (available from most DIY stores).
Measure the appropriate volumes and mix thoroughly. Slowly add water and continue to mix. Aim to add just enough water to completely wet the mix, but not so much as it goes ‘sloppy.’
TIP: Use gloves when handling the mix. Cement and wet hypertufa are corrosive and strong skin irritants.
You can create a sink in many ways. Below are some of the preferred methods used by alpine enthusiasts:
Expanded polystyrene fishboxes are widely available. They’re excellent for creating a light but robust sink.
This process is similar to fishboxes, but it can be tricky to get the mixture to stick to the glazed surface.
Casting a solid sink is the traditional method.
The mix sets slowly, so cover with damp hessian sacking or a polythene sheet for a day or two. You can then remove any cardboard boxes.
Genuine stone troughs tend to have irregular surfaces. To create an authentic finish, (when still slightly soft) strike the surface with a steel chisel, broad screwdriver or scrap of wood.
Round off any sharp edges by rubbing over with a stiff brush.
The hypertufa will continue to cure and harden over the next couple of weeks. Wait until your sink is fully cured before moving it to its planting position.
You can also use the hypertufa recipes to create tufa-like rocks.