PASTEURIZE COMPOST BEFORE
USING FOR POTTING SOIL
A REAL DISEASE
ANNA MAY KINNEY
gardening bug has not bit yet, watch out, it wont be long. One of the first signs is
the insatiable desire to fill every usable container with potting soil.
flowerpots lined up on every windowsill, seed packets piled high on the table, and a
bucket of clean pasteurized compost behind the wood stove, theres no doubt its
anything that holds soil will work, even used yogurt containers with drainage holes can be
used. Make sure that all containers have been cleaned out and sterilized since the last
time they held soil. Now youre ready,
exactly, without the proper care when choosing a potting mixture, you could wind up with
some unwanted stowaways. The fungus, bacteria and viruses that can be hidden in garden
soil and compost can quickly wipe out weeks of work.
remember waking up one morning, about thirty-five years ago and finding all my three-inch
tomato plants laying on the ground, it looked like something had eaten away the bottom
section of their stems.
knowing about the dangers of using my own soil and compost, I had gone out and brought in
a pail full of infected potting soil and what happened next is called damping off.
are infected with damping off will not germinate and plant stems shrivel causing seedlings
to topple over and die. If you have waited an unusually long time for a particular seed to
germinate, brush the soil away and carefully take a peak. If it is dark and mushy it has
damping off and the only thing left to do is start over, this time with clean potting
This problem happens everywhere things grow, no
matter where you live and there is absolutely no remedy once plants and seeds are
infected. The answer is prevention.
people choose the safest route, buying a pre-sterilized package of potting soil, if you
have a large amount of pots and flats to fill, this could be expensive. By taking a couple
of extra steps before you begin, you can use your own rich, organic compost.
heard people tell of how they bake their soil in their oven to kill
micro-organisms, this process of sterilization kills everything, even the healthy
organisms that you have worked so hard to create.
is simple; instead of sterilizing compost and garden soil, pasteurize it.While sterilizing
kills virtually all surface-dwelling microorganisms, when you pasteurize your potting
mixture, it is only heated to a temperature that kills harmful organisms and leaves
beneficial organisms alone.
To pasteurize, take a large aluminum-baking pan
and cover it with three to four inches of potting soil, insert a meat thermometer in the
center and place in a preheated oven, at 200°F., once the
center reads 160°F., bake for 30
minutes. Allow mixture to cool thoroughly before using.
other pitfalls to avoid when starting seedlings. Water pots and flats in the morning or
early afternoon, and avoid leaving them where the night temperature falls below 50°F.
If using a
southeast windowsill check pots often, most seeds are only ¼ of an inch or less from the
surface and when the surface dries out so do the seeds. A couple of hours without moisture
will quickly destroy anything that has sprouted.
are limited on window space, you can actually start a dozen tomato, eggplant or pepper
plants in one pot. Theyll be ready to be divided when they are about two inches
high, its easy to separate plants at this stage and they seldom suffer from the
to separate, place them in individual pots, taking off the two lower leaves. Bury the tomatoes all the way to the top leaves,
this will encourage them to build a stronger root system right from the start. The peppers
and eggplant are not buried any deeper than they were in the original pot.
have reached six inches high, I repot the tomatoes again, burying most of the stem. This
is where having a good supply of tall cans comes in handy. By the time they are ready to
set outside they have developed thick, strong stems with a magnificent root system.
When its time to take them out of the can
and place them outside in the garden, dig the hole almost the same height of the tomato
plant you are putting in, and take off all but the top two or three sets of leaves, now
bury him right up to the last set of leaves. Youll only have a tiny plant showing,
but there will be nothing above ground for this plant to waste energy on, it will use all
its energy growing a strong root system.
short plants also makes them easier to protect from an unexpected frost on those first
nights outside and in no time their strong root system will produce strong healthy
branches, and youll have the best tomato plants ever.
plants should be fertilized lightly, or youll wind up with huge bushy plants and few
fruit. At the first signs of blossoms I side dress each plant with a good serving of
well-aged manure and rich compost.
seem a bit early, but it is nice to start a few lettuce seeds. While they are growing
there is plenty of time to put together a small cold frame. Setting your young lettuce
plants into a cold frame around the 15th of April, youll be eating fresh
salad greens while everyone else is planting seed.