Answer: There are some in my area, too. They really are the old half whiskey barrels tipped and supported/immobilized from behind with rocks or bricks or whatever, partially filled with a slope of potting mix, and planted. Plants are also set out in the surrounding ground to mimic the effect of a pool of water. They work best with impatiens if oriented so that the opening faces north or east as impatiens are typically shade to part shade plants. (They can be grown in sun with ample watering, however.) Spacing will depend on the variety of impatiens you select, however a rule of thumb would be to put them fairly close for a full effect early in the season, perhaps setting them about 8 inches apart if their estimated final height is 12 inches. If you get very involved in the project, you can plant taller varieties to the rear and shorter ones to the perimeter to further enhance the effect of spreading water.
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