The first step in making a cactus garden is, of course, to plan it out. Scout out a location in your yard for your garden. The optimal place for a cactus garden is on hill, because this allows the garden bed to easily drain. You can still make a cactus garden if your yard is flat, you will just have to do more digging.
When you decide where you want your cactus garden, decide what size and shape you want. Use your imagination and be creative; you can have a circle, square, rectangle, semicircle, triangle, whatever you desire. Then mark the border of the garden onto the ground before you begin, this will make the digging much easier.
Digging, the dirty part
Now for the digging. If your garden is going to be on a hill, you have it pretty easy. You need to level out the ground where your garden is going to be, digging into the hill on the upper end of your garden. You will also need to dig a few inches of earth up over the entire base of the garden to remove all the grass and weeds that would harm the cacti. The area does not have to be perfectly level, you just don’t want any big bumps that will make your garden uneven or any foliage that will prevent proper drainage and cause your cacti to rot.
If you don’t have a suitable hill to place your cactus garden on, choose any spot and decide the shape and size of your garden. After marking the borders of the garden onto the ground, dig out 6″-12″ of earth.
Gathering the materials for the garden
Now that you have finished digging, you are ready to begin constructing your garden. First you will need to get outdoor tile blocks or stones to build a wall around your garden. Although the tile blocks come in a variety of styles and are very beautiful, they are also very expensive.
If you are willing to foot the expense, these tile blocks can be purchased at garden centers and home improvement stores. Rocks work just as well and also look beautiful and more natural and are much less expensive. I suggest using rocks, which you can buy or find yourself.
You will also need a strip of plastic equal to the length of the border of your garden. Any plastic will do (it will not be seen), such as an old tarp. The plastic is optional, but it eliminates weeds and it will save you a lot of time and backaches.
Cactus soil is also another necessity. You will need enough to fill your garden to the top of the wall. You will have to wait until after construction of your garden to see how much soil you will need. You can purchase cactus soil at your local gardening center or home improvement store. If you cannot find any cactus soil, you can make your own by thoroughly mixing two parts potting soil, two parts sand and one part gravel.
The first step in building your garden is to cover the edge of the grass with the strip of plastic. This will help prevent weeds from spreading into the garden bed. Next, stack your rocks or tile blocks along the edge of the garden. How high you decide to make the wall is up to you, but 12′ works well. After building the wall, you should fill your garden with the cactus soil.
Now comes the fun part, planting your cacti. Choose plants that will do well in your area. You should be able to get this information wherever you buy your cacti. If you live in an area where the temperatures fall below 45 degrees Fahrenheit, there is an easy way for you to still have a cactus garden. Plant the cacti, pot and all, in the ground. Then when wintertime rolls around, you can simply lift your plants out of the ground and bring them inside to wait until spring.
When planting your cacti, be creative in your design. You can plant the cacti in a pattern or randomly, however you choose. After you have finishing planting your cacti, your garden is complete.
Your cacti garden will need very little maintenance. No watering or irrigation is needed, the rainfall will be enough. Feeding your cacti with 10-10-10 fertilizer once a year in the spring is the only thing you will need to do.