Q. I have a cactus I bought as a start from a little
nursery in 29 Palms that grew a foot a year for the last 15 years. It finally tore
out of the ground and fell over causing the ground to quake. It towered to 17′
and was spectacular. The cactus had no water supply but was irrigated by water
runoff from the roof.
nursery in 29 Palms that grew a foot a year for the last 15 years. It finally tore
out of the ground and fell over causing the ground to quake. It towered to 17′
and was spectacular. The cactus had no water supply but was irrigated by water
runoff from the roof.
 |
| Not this readers cactus but another cactus which is blown over because the roots have not spread out due to localized irrigation. |
A. I suspect the cactus had a very small, spreading root
system that finally just couldn’t support it anymore and fell over because it
was top-heavy. Cacti and other desert plants have extensive, relatively shallow
roots, that spread as much as eight times their height! This extensive root
system provides a very efficient way of gathering sparse rainwater and provides
substantial support for taller cacti.
system that finally just couldn’t support it anymore and fell over because it
was top-heavy. Cacti and other desert plants have extensive, relatively shallow
roots, that spread as much as eight times their height! This extensive root
system provides a very efficient way of gathering sparse rainwater and provides
substantial support for taller cacti.
Non-desert
plants, sometimes referred to as “mesic” trees and plants, are reported to have
spreading roots as much as 2 to 3 times their height. Still quite extensive but
not like desert plants. Cacti have more extensive roots that are not terribly
deep for gathering sparse rainwater as quickly as possible. Desert plants
convert this unexpected water into rapid growth and producing flowers. They are
good at that.
plants, sometimes referred to as “mesic” trees and plants, are reported to have
spreading roots as much as 2 to 3 times their height. Still quite extensive but
not like desert plants. Cacti have more extensive roots that are not terribly
deep for gathering sparse rainwater as quickly as possible. Desert plants
convert this unexpected water into rapid growth and producing flowers. They are
good at that.
Water cacti infrequently but in a large area
So, I
think it’s important to periodically irrigate cacti large distances from the
mother plant as they get taller. Plants get water where it’s the easiest to
find it. Desert plants are opportunists. By that I mean, when water is present,
they grow quickly and then shut down when water is no longer available.
think it’s important to periodically irrigate cacti large distances from the
mother plant as they get taller. Plants get water where it’s the easiest to
find it. Desert plants are opportunists. By that I mean, when water is present,
they grow quickly and then shut down when water is no longer available.
By watering
these plants close to their base (e.g. rainwater from the roof) they tend to
fall over as they get taller because the small size of the roots can’t support
its massive top growth. Of course, I’m not mentioning how often you should
water these plants. That’s an entirely different topic. But when they are
irrigated, water should be applied over a large area.
these plants close to their base (e.g. rainwater from the roof) they tend to
fall over as they get taller because the small size of the roots can’t support
its massive top growth. Of course, I’m not mentioning how often you should
water these plants. That’s an entirely different topic. But when they are
irrigated, water should be applied over a large area.
I probably
don’t need to tell you that plant roots don’t actively “seek” water,
but they grow towards sources of applied water because of soil moisture. With
cacti, and many of the other succulents, it doesn’t take much soil moisture to
get them growing in its direction.
don’t need to tell you that plant roots don’t actively “seek” water,
but they grow towards sources of applied water because of soil moisture. With
cacti, and many of the other succulents, it doesn’t take much soil moisture to
get them growing in its direction.
In my
opinion, I think it’s beneficial to use a hose and hose-end sprayer
periodically and spray the surface of the soil around cacti to get their roots
spreading outwardly and anchor them in the soil as they become larger. Of
course, water should be applied at times of the year, or in intervals, that
don’t encourage Bermudagrass growth, a terrible scourge to landscapes.
opinion, I think it’s beneficial to use a hose and hose-end sprayer
periodically and spray the surface of the soil around cacti to get their roots
spreading outwardly and anchor them in the soil as they become larger. Of
course, water should be applied at times of the year, or in intervals, that
don’t encourage Bermudagrass growth, a terrible scourge to landscapes.