How to make a grotto
Perhaps you are lucky enough to have a natural stone formation that can be used as a grotto. If not, how would you go about constructing one? Here is a checklist on how to make a grotto. We hope that you find it helpful. But here we will share a few notes about grotto construction to consider.
Start with a pile of rocks
Grotto construction can be a simple matter of piling rocks into a structure, however this could be a safety risk because the rocks could collapse and cause damage, injury, or death. Bricks or landscaping pavers could also be used as part of the structure. Again, if you just stack these materials with or without rocks and soil, be careful of the safety of your construction.
Use mortar to keep the rocks together
A significant enhancement to the stability and safety of a grotto can be achieved through the use of mortar. This video describes the fundamental differences between cement, concrete, and mortar. You can apply mortar between the stones or bricks as you build your grotto. The mortar helps hold the structure together. If you plan to add significant strength to the structure, consider using concrete, as noted in the video earlier in this paragraph.
Use steel reinforcement bars (rebar) for strength
Although it is less simple and natural than a pile of rocks or a stack of bricks, you could build an artificial grotto structure using concrete. In order to shape the concrete into creative or natural looking structures, you could use steel reinforcement bars (rebar) to create the desired shape and add strength to the structure. Such strength is especially important if you will ever climb or walk on the grotto structure such as to tend to the plants you may have growing on it.
Skilled construction workers and landscape engineers may use burlap, plastic or metal screen, chicken wire, and other materials around the rebar to help shape the concrete that is used to build the structure. An example of this is shown in this video showing a preparation stage of an elaborate grotto construction.
Before building the grotto structure, you may wish to add plumbing inside the grotto structure, or craft water channels in the surfaces of the structure. You can transform a simple stone or concrete grotto structure into a fountain or waterfall by using appropriate plumbing and water channels. This can also be useful for irrigation of plants that grow in and on the grotto.
Some people like to build grottos as a simple stone shrine. Transforming the grotto into a water feature should be planned ahead if at all possible, though water could be retrofitted into some existing grotto structures. Whether you build your main structure of stone, brick, reinforced concrete, or a combination of these, you can incorporate plants into your design. Be sure to accomodate enough space in the planting portions of your design for adequate soil, water supply, root structure, and drainage.
Ferns, grasses, reeds, bamboo, all varieties of tropical plants, and flowers are popular kinds of plants to include in a grotto. In some cases the same plants could survive through the life of the grotto. It is possible to replace old flowers with new ones on a regular basis. And you could change the types of plants in the grotto over time. Depending on your balance of the grotto elements—the fundamental structure, shrine, water, and plants—you could create a garden that features your grotto or even a garden within the grotto. Whether you build a garden grotto or a grotto garden, we hope you enjoy your creation.
Do you have any favorite grottos that you like to visit? A quick web search can reveal a wealth of photos of grotto gardens. Do you have a design that you would like to build some day, or perhaps photographs of a grotto you have built?