| I was inpired by the amazing artists/garden sculptors Lewis and Little and started to look for ways to recreate their work. If you have not seen their work you should check it out on their website: http://www.littleandlewis.com/
Found this recipe for making columns:
COLUMN
Tools:
Posthole digger, level, shovel, deep wheelbarrow, piece of rebar or PVC pipe, concrete trowel
Materials:
8 60-pound bags ready-mix concrete
12-inch-diameter cardboard tube (made for pouring concrete; available at home improvement stores)
Exterior latex paint
Paintbrush
Soft cloth
Steps:
1. Decide where you want the column, keeping in mind you won't be able to move it and it's there to stay.
2. Dig a 2-foot-deep hole with posthole digger; it will be about half the diameter of the cardboard tube. Dig a shallow (4 to 6 inches) depression around the hole. Center tube over hole. Use level on two sides to see if tube is level. Dig out depression in high spots until tube is level. Set tube aside till step 4.
3. Put on face mask. With shovel, mix two bags of concrete in wheelbarrow. Follow directions on bag for amount of water. Add water a little at a time; it's easier to add more water than more concrete. Keeping it on the dry side (looks something like cottage cheese) makes for a more distressed-looking column; a wetter mixture (like oatmeal or cream cheese) results in a smoother finish. If you like, make some batches wetter and some drier for different effects.
4. Fill hole in ground with concrete. Center tube over hole, checking level once more. To keep tube in place, backfill around it with dirt from depression.
5. Fill tube with wet concrete. Using rebar or PVC pipe, pierce concrete to help settle it.
6. Keep mixing concrete, two bags at a time, and filling tube. When you get to the top, smooth with trowel.
7. Let stand 24 hours. Starting at the top, peel tube off.
8. Let cure one week.
9. Paint with a wash of one part latex exterior paint mixed with two parts water (this mixture is imprecise; you can experiment until you find what you like). Use cloth to blot paint. More than one color adds depth and interest.
10. Make additional concrete pieces for the top with plastic pots or plastic saucers as molds (or whatever shape you like). Spray mold with cooking oil (such as Pam) and fill with wet concrete. After 24 hours, pop out of mold and follow curing and painting directions above.
11. Attach decorative concrete pieces to the top of column with mortar.
12. Top with potted plant or piece of art.
Variations:
To place your column on a patio or other hard, flat surface, you need to make a base. Build a frame for one out of 2-by-4s. Make sure it is in proportion to the column and big enough so the column won't tip or rock. Pour column in place, making sure it's positioned exactly where you want it. After 24 hours remove cardboard tube. Then slip base frame over top of column and center around bottom of column. Pour base. Cover wet concrete with plastic for 24 hours. Knock off wood framing. Wait one week before painting.
If you want a taller column, you're on your own. We're pretty sure they're made in sections, hollow in the center and then stacked. Rebar goes down the center and more concrete added. But beware, the higher you go, the bigger the chance of engineering mistakes. | 
