Q. I read about air pruning the roots of potted plants
using either fabric pots or drilling holes in pots and lining with landscape
fabric. Supposedly, air pruning keeps
the roots in “check” so that they do not outgrow the pot. The idea sounds logical, but with our extreme
heat and hot winds, could this work in Vegas?
using either fabric pots or drilling holes in pots and lining with landscape
fabric. Supposedly, air pruning keeps
the roots in “check” so that they do not outgrow the pot. The idea sounds logical, but with our extreme
heat and hot winds, could this work in Vegas?
A. Air pruning is allowing the roots of plants are
exposed to the air and die. It is normally used in greenhouse production with
potted plants. It can be used for plants growing in containers as well. It is
popular where other types of root pruning may not be practical.
exposed to the air and die. It is normally used in greenhouse production with
potted plants. It can be used for plants growing in containers as well. It is
popular where other types of root pruning may not be practical.
If
plants grown in containers are allowed to rest on soil or gravel, the roots of
these plants can grow out of the holes on the bottom or sides of the container
and into the wet soil beneath it. Once the roots leave the container and grow
into the soil, the tops of these plants typically have big growth spurts.
plants grown in containers are allowed to rest on soil or gravel, the roots of
these plants can grow out of the holes on the bottom or sides of the container
and into the wet soil beneath it. Once the roots leave the container and grow
into the soil, the tops of these plants typically have big growth spurts.
In the
past, if these pots or containers were given a quarter turn twist, this would
sever young roots and prevent them from getting anchored in the soil beneath
them. This is an older method of root pruning.
past, if these pots or containers were given a quarter turn twist, this would
sever young roots and prevent them from getting anchored in the soil beneath
them. This is an older method of root pruning.
Another
older form of root pruning was using chemicals such as copper sulfate applied
to the surface of the soil or gravel just under the pots or containers. The
concentration of copper would kill the roots of plants growing into it but
would hurt the tops of the plant.
older form of root pruning was using chemicals such as copper sulfate applied
to the surface of the soil or gravel just under the pots or containers. The
concentration of copper would kill the roots of plants growing into it but
would hurt the tops of the plant.
Air
pruning is another form of root pruning where the bottoms of containers are
pots are suspended in open-air. Roots exposed to the open-air will die without
moisture. As roots leave the container through drainage holes, the roots die
and become “root pruned” by the air.
pruning is another form of root pruning where the bottoms of containers are
pots are suspended in open-air. Roots exposed to the open-air will die without
moisture. As roots leave the container through drainage holes, the roots die
and become “root pruned” by the air.
This
would work in our climate as well. However, in our hot desert climate I worry a
bit about pots or containers left in full sunlight. The soils in these
containers can heat up quickly and the roots “roasted” on the side of the container
facing the sun.
would work in our climate as well. However, in our hot desert climate I worry a
bit about pots or containers left in full sunlight. The soils in these
containers can heat up quickly and the roots “roasted” on the side of the container
facing the sun.
If pots
or containers that you are using for root pruning are in full sun make sure
they are white or shiny and reflect as much sun as possible. It would be best
if they were shaded. Water the plants in the containers just before the heat of
the day.
or containers that you are using for root pruning are in full sun make sure
they are white or shiny and reflect as much sun as possible. It would be best
if they were shaded. Water the plants in the containers just before the heat of
the day.