How to Prepare a Concrete Pond for a Pond Garden

Adding a garden pond to your current landscape will instantly perk up the space. Although plastic liners can be purchased to make a garden pond, these will eventually wear out and need to be replaced. Constructing a garden pond with a concrete base will ensure the feature will provide years of enjoyment. In addition, although the garden elements of the pond will need to be maintained, the concrete foundation will not require regular repairs, saving you further time and energy.

Things You'll Need

• Spray paint
• Shovel
• Cement mixer
• Hose
• Bucket
• Level tool
• Polythene sheet
• Gravel/sand mix
• Cement mix
• Flat stones

Instructions

1. Choose the area where you want to put in the pond. Level the ground and mark the outline on the ground using spray paint.

2. Dig a "shelf" about 8 inches wide and 2 inches deep around the perimeter of the future pond. This is where the decorative stones will be placed.

3. Remove the dirt in the area marked with the spray paint to create a bowl shape no more than 16 inches deep. The hole should slope gradually downward from the edges and should be deepest in the center.

4. Place a polythene liner over the area that's been dug out, covering the entire interior and draping over the edge with at least six inches of excess material hanging beyond the outer edge of the shelf.

5. Mix the concrete in a mixer or a wheelbarrow with the ratio 1 part of cement to 4 parts of gravel/sand mix, adding enough water to make a slightly stiff mixture.

6. Spread the concrete a minimum of three inches thick over the liner, beginning in the center of the pond and working your way outward toward the shelf.

7. Place the flat stones into the concrete, pressing down slightly.

8. Fill the pond with water. Allow to set for a week.

9. Drain the water and add fresh water, along with white vinegar, to the pond. The ratio should be 1 gallon of vinegar for every 200 gallons of water. Allow this solution to penetrate the concrete and dissolve the lime that can be toxic to pond life. Empty the pond after three days. Rinse, refill and add plants and fish.

Tips & Warnings

• Large stones can be used to create a ledge over the water that can provide protection from the sun for fish. The pond should not be paved in sections, as it must not be allowed to harden completely before filling with water. If necessary, sprinkle the cement with water each hour to prevent from drying.

• Do not use a regular trowel when spreading the cement, as it may pierce the liner. A block of wood may be used instead.

References

• Preparing a Concrete Pond
• More Concrete Pond Tips