Creating concrete trough planters is a straightforward procedure that just about anyone can do. When attention is paid to detail, the results can look just like natural rock and blend perfectly into the landscape. When properly sealed the concrete troughs can even hold water acting as raised ponds and water gardens. Concrete is just the thing to use when economical and customisable planters are desired for the garden or home.
Clean the barrel thoroughly with soap and water. Avoid using abrasive scrubbing pads as they may mar the surface of the mould. Rinse well and allow the barrel to dry thoroughly.
Coat the mould with a thin layer of petroleum jelly making certain to get into every detailed area. If an area is missed, it will make for a difficult time in removing the finished product from the mould.
Mix the concrete and water with a shovel as per the manufacturer's directions in a large container. Work quickly while making sure there are no dry lumps of concrete in the finished product. Add the concrete colourant to the mix and stir well until it is evenly distributed.
Pour a ½-inch layer of cement in the bottom of the largest barrel mould. Spread the chicken wire evenly across the top of the cement and up the sides of the mould. Several layers of wire may be used to give added strength to the finished product. Be careful that as much of the wire as possible is covered with cement.
Place the smaller barrel (rounded side facing the concrete) centred within the mould. Pour concrete around the sides of the smaller mould so that it fills the entire planter area. Tamp the concrete down as you go with a board to remove air pockets. A rubber mallet can be used to tap the sides of the mould to remove remaining air.
Allow the concrete to set up; it should be firm enough that removing it from the mould does not break it. Once removed from the mould use a drill to create drainage holes throughout the bottom of the planter. Go over the entire pot with a stiff wire brush to roughen up the surface and remove loose cement particles.
Place in a protected area covered in cling film for one week. If allowed to dry too quickly the concrete may cure in a weakened state and the trough might break. Once the concrete has fully cured and dried, it can be planted in.
For larger projects where a ready-made mould is not available, the ground can be used as a mould. Dig the size and shape you want for the finished pot directly the ground. Line this hole with plastic to aid in removing the dried pot. Pack the concrete mixture around the reinforcements, cover and allow the pot to dry. For larger pots and troughs, two or three people should help lift them from the ground.
Always wear gloves when working with concrete. The substance (dry or wet) is caustic and harmful to exposed skin. The use of a mouth and nose-covering mask is recommended, as the dust from concrete is just as harmful to your lungs as it is your skin.