I decided to try my hand at a simple project: create a medium-size concrete herb pot with two separate areas, one for lemon verbena and one for mint. Mint should generally be separated from other herbs as their root system is extensive and can "take over" if you're not careful. To my shock, this book's instructions were pretty accurate, and the project took less than an hour, excluding drying time.
Making this herb pot is a lot like baking. Getting everything ready, follow the instructions and then work in the right order. For this project, you'll need concrete (quick mix concrete works as does the more commercial concrete), water/hose, a paint brush, cooking oil, a large container and two small containers.
Additionally, if you want drainage hole, use a straw or a found object to mark the hole and ensure concrete doesn't enter the area. It also helps to have a cinder block or heavy weight around -- but rocks work well for this purpose, too. Ensure you have a clean and level workspace; preferably a waist high table, like a potting table.
Setup For this project, you'll need one larger container and two small containers. Make sure that the two small containers fit comfortably inside the large container. The large container is your main mold, so there needs to be space for sturdy walls to form between the objects. The smaller containers are the interior molds. I used some terra cotta- colored "pots" made of sturdy plastic found at a local hardware store. An advantage here is that they already had openings for drainage and they came in a variety of sizes.
First Steps Use a paint brush to thoroughly coat the inside of the larger mold and the outside of the smaller molds with cooking oil. It's just like baking; anywhere there is oil- the concrete won't stick. Now, mix up your concrete. It's roughly two parts concrete to one part water, the final product should be like a thick batter. Keep in mind that concrete, especially here in dry Arizona, sets quickly. I mixed my concrete with a garden spade in an old bucket.
If you're making drainage holes, decide now where you're going to place the straws; it's a good idea to slide them into place and have a friend hold them in place while you pour concrete. If you use something more substantial like a pipe, you may not need help. Either way, ensure they are "oiled up."