On Friday, July 5, 2013 4:08:42 PM UTC-7, David Hare-Scott wrote:
Higgs Boson wrote:

I had always snobbishly regarded potting soil as something marketed

to apartment dwellers or people who didn't understand gardening.



Now have to re-evaluate.



I made a rectangular planter in wood shop years ago. About twice the

size of the redwood planters sold in stores. Today gardener helped

me get it back on wheels (from which a (*&^%#%&* person had removed

it -- don't ask!!). Very heavy.



He said it was because I was using ordinary garden soil; said potting

soil would be much lighter. Said it would work just as well.



QUESTIONS: a. Is potting soil just as good as garden soil (assuming

garden soil is OK)?



b. Is it worth replacing x% of garden soil with potting?



c. Or remove and replace all?



d. Leave it alone.



I am NOT looking for work!!! Planter is back on wheels and can be

moved, with some difficulty. For now, just asking if anyone agrees

with gardener's opinion potting soil vs garden.



HB



Potting mix is often lighter as light components are added (eg expanded

minerals) and many contain quantities of shredded bark etc which is also

less dense than garden soil.



Whether potting mix or garden soil are equally suitable depends on the

quality of both and what you are trying to grow. I would expect some garden

soil (with a good amount of clay and organic matter) would hold both water

and nutrients better than potting mix which is often low on clay and

confected to be light and very free draining. In principle the garden soil

would require less watering and feeding but this may not be an issue.



If you are going to be moving the tub frequently and the weight is a real

issue then consider replacement. Otherwise provided the drainage is

adequate and the plants are doing well don't bother.

Helpful replies from you and Songbird. I wouldn't have thought of filling the bottom with space-holding materials, e.g. Also David I didn't know what actually goes into making commercial potting mix.

OK, what's in the planter is just flowers (marigold at the moment) and maybe perennials in future. Nothing portentous that would need great depth.
Drainage is good.

I was mainly curious about an unknown (to me) quantity like potting mix as a LONG TERM solution. My gut sort of told me to stay with my own mixture. Planter is back on wheels and can be moved in the unlikely case...

As to size, Songbird, I said it was about twice the size of the redwood planters sold in garden stores.

Tx

HB