(Editor's Note: This article was originally published on April 5, 2007. Your comments are welcome, but please be aware tha authors of previously published articles may not be able to respond to your questions.)

The rule of thumb for establishing new plants is to:

  1. Water every 3 days for 3 weeks
  2. Water every week for 3 weeks
  3. Water every 2 weeks for 3 weeks

It is the middle of July where I live, and we have not had a soaking 2 hour rain in 5 weeks. Obviously, I need to use supplemental water. I am on a well, not City Water, and my well refill rate is one gallon every half minute. In case it is not obvious, I have very little water (beyond house hold use). I had to think of something, to water my new ground covers, but not waste water (such as an overhead oscillating sprinkler would). Drip irrigation is one idea, but I didn't want to install a drip irrigation system for plants that will only need supplemental water their first 2 or 3 seasons.

Thus, I came up with the idea of "collars".

I will plant the plants each with little collars double the dimension the pot the plant came in. These collars will serve to get the water to the roots, rather then just run off. I will be using roofing flashing as the collars for the bigger plants, and heavy weight roofing felt paper as the collars for the smaller perennials.

A picture is worth a thousand words:


These pictures are of a newly planted 3.5 inch Ice Plant, and that very same Ice Plant overgrowing it's collar (which is as I hoped, but I wasn't sure).

The Calculations

Double the dimension of a 3.5 inch pot is 7 inches. You then need the circumference to make the collar. The formula for circumference is PI (3.14159265358979323846) times the 7 inches, which is double the dimension of my original pot size, the plant came in, which equals roughly 22 inches as the circumference. My roofing felt is 36 inches wide, so I cut off a rectangle the 36 wide by 22 inches. I can then divide the 36 inches in 12 - 3 inch collars, or 9 - 4 inch collars. (I used 3 inch collars this season - half in the ground, half not, but I am inclined to make 4 inch collars next season.

Article first printed at http://www.reply42.com/garden/collars.php full permission granted to Daves Garden for reprint.