Reusing container soil
 

Thinking ahead to next year...

Any reason I can't reuse the soil from this year? I built a sieve out
of 1/4" hardware cloth. At the end of this season, I can just toss the
dead plants, then sift the remaining dirt to get rid of roots and
other debris and reuse it next year.

Reusing container soil
 

On 2009-04-05, Richard Evans wrote:
Thinking ahead to next year...

Any reason I can't reuse the soil from this year? I built a sieve out
of 1/4" hardware cloth. At the end of this season, I can just toss the
dead plants, then sift the remaining dirt to get rid of roots and
other debris and reuse it next year.

For plants like tomatos, you would have to consider soil rotation
perhaps since some of the diseases stay in the soil and get worse if the
same thing is replanted each year. This only applies to some crops
though.

a crop failure would be a sign of dumping the soil. With care you
probably can minimize the contamination problems or get a couple years
out of it.

I do it with flowers, but mix it 50/50 with new potting soil each year.

--
Wes Dukes (wdukes.pobox@com) Swap the . and the @ to email me please.

is a garbage address.

Reusing container soil
 

On Sun, 05 Apr 2009 18:26:57 -0400 in Richard Evans wrote:
Thinking ahead to next year...

Any reason I can't reuse the soil from this year? I built a sieve out
of 1/4" hardware cloth. At the end of this season, I can just toss the
dead plants, then sift the remaining dirt to get rid of roots and
other debris and reuse it next year.

Do you mean dirt, or do you mean potting mix?
I ask because most dirt doesn't work very well in a container.

As for reusing problems.

1) Disease. If the plant picks up a blight, a fungus, a virus, or
other pest, it'll be there in the soil again next year.
Plus you've had all season to pick up lots of fungus spores
that all want to take a try at eating your plants.
It's sort of the difference between stepping on a dog turd and
going swimming in a cess pool.

2) Insects. Insects will lay their eggs in soil. Reusing it without
providing them a growing season or few with something unpalatable
means more insects the following year.

3) Weeds. You've had all season for wind and animals to deposit weed seed.
Plus your vegetables can quickly turn into weeds. Last year I put out
some potting mix that had tomatoes and tomatillos growing in it in 2006.
And the bed was promptly over taken with tomatillos. I grew a variety of
banana pepper last year that produced faster than i could keep after it, and
now I have a bed full of pepper seedlings as weeds.

4) Tilth. By growing in containers you have a harder time keeping
the media/moisture/air ratios right (Hence the use of a potting mix
instead of soil). Coarse airy materials such as bark and coar
decompose making for a more compact soil. Roots remain and decompose
changing the ratio between dense bits and fluffy stuff like vermiculite
and perlite. The moisture control mixes also include the same polymer
used to make diapers and sanitary napkins extra absorbent, and various
good bacteria break that down releasing the water.

5) Nutrition. The cheap potting mix I mentioned has slow release fertilizer
in it. The plants suck up nutrients, and different plants have different
nutritional needs.

If I were growing a lot in containers, I'd probably look at using
heat/steam to sterilize the old mix, mix the whole batch thoroughly,
and send a sample off for soil test before ammending for the next season.

Of course if I had the means to mix it all thoroughly, I'd probably
just buy compost by the yard and vermiculite by the pallet, and use
the previous year's mix for top dressing my lawn.
--
Chris Dukes
davej eskimos have hundreds of words for snow. I have two. Bullshit.

Reusing container soil