Q. I have a
beautiful container that lacks drainage holes in the bottom. I would
like to plant a cactus in it. Can I just fill the bottom with gravel
to provide drainage?
Placing gravel on the bottom of a solid container to improve
drainage is one of
the most common misconceptions about container-grown plants.
Gravel in the bottom of a solid container actually decreases the
soilís ability to drain. To prove my point, get an ordinary
sponge and saturate it with water. First, hold it over a sink
lengthwise and see how quickly the water drains from it. Then
saturate it again, and hold it widthwise over the sink, and see how
much less water drains from it than when you held it lengthwise.
Finally, saturate the
sponge again, and hold it flat over the sink, and see how almost
no water drains from it.
How does soil
Soil works much like the sponge. The longer the soil column, the
better it drains; the shorter the soil column, the less it
drains. By placing gravel in the bottom of a container, you are
shortening the soil column and reducing its ability to drain.
Flower pots usually come with drainage holes
solution is to get a plastic pot with drainage holes in it that
will fit inside your decorative container. Pot the cactus in the
plastic pot, and then place the potted plant into your solid
container. Whenever you water your cactus, be sure to take it
out of the solid container and place it in a sink or bathtub
until the excess water drains. Then return it to its decorative
container. Never allow it to sit in excess water collected in
the bottom of the solid container. Cacti (and most other plants)
are susceptible to root rot in such a situation.
Blueberries in containers
What works best for Sand Mound