The formation of tufa

When calcium enriched spring water comes to the surface it sheds the excess calcium, forming solid deposits on surrounding plants, grasses and mosses. When the foliage deteriorates, it leaves a sponge-like structure that is rich with nutrients. This is called tufa. Often you will see fossils of leaves, twigs, roots and grass on the rock. Tufa has been regarded as one of the most effective materials for growing many demanding alpines.


The characteristics of tufa

• Tufa is the only stone that will actually support growth.
  
  
• It is about 40% of the weight of ordinary rock, so most pieces can be placed by hand without the need for machinery.
  
  
• Moss can be introduced to the tufa rocks. In our gardens this happens naturally.
  
  
• Tufa is like a sponge. It absorbs water easily and quickly.
  
  
• Once it is wet, tufa can be easily shaped using the most basic tools, such as a screwdriver or a drill.
  
  

PLANTING IS EASY

• To gauge the size of the hole needed, the tassel of roots should be drawn loosely together, indicating a suitable diameter and depth.
  
  
• Pot-grown stock should have most of the soil shaken or washed from the roots. The tufa debris from the holes should be mixed with twice its bulk of potting soil for working around the roots after inserting.
  
  
• Bury approximately one third of the tufa in earth. The rock will act as a sponge, drawing moisture upwards from the ground. For a few weeks, the newly inserted plants will require regular watering. Surrounding plants are a good indicator. In no time, the roots will be off exploring the labyrinth of holes. Occasionally, lost roots will resurface, giving the tufa a unique look.
  
  

Plants for tufa