So, you've heard about flushing, but you wonder why, right? Okay,
let's paint a picture of what happens in nature to give us a comparison.
In nature, the rain droplets, (formed high in the atmosphere and
highly oxygenated ) collect into droplets heavy enough to start falling
earthward, and eventually reach the earth where the plant is growing.
The rain soaks the soil surrounding the soil, and releases the
oxygen collected during the water droplet's fall.
Gravity continues to pull the water downward through the soil to the
watertable, washing all accumulated plant wastes downward with it and
away from the roots.
At the same time, the rain also helps break up and bring down fresh
nutrients from the top of the soil. In this way, there is never any
build-up of toxic wastes to prevent the normal function of the roots,
and they get fresh air, water and nutrients with each rain. Meanwhile,
back at the ranch, we have to find a way to bring conditions in line
with what is going on out in nature. Inside the pot, the fertilizers and
plant wastes have no place to go, and become concentrated in the bottom,
which raises the ph to toxic levels. This causes what is known as
nutrient lock and the plant can't get any nutes. It's important to flush
on a schedule to keep the pH balanced, and remove the wastes excreted by
the plant. Expect to need a gallon or two at least for each plant, so
bubble the water in advance, and make sure you have enough to do the
whole job at once.
Here's a shot
of another good method for flushing plants in 6 inch flower pots. Two
can be done at a time, and the color of the effluent being rinsed from
the plants systems can be easily seen in the bottom of the white bucket.
At around 2 to 3 weeks, the plant will need its first flush, and
nutrients lock up and become unavailable for the the use of the plant.
Simply pour the water through the top of the pots, and observe the
Here's a good shot of the deep yellow color of the water just
flushed through 3-week old plants in 6 inch pots. No surprise that the
plants shown here were not responding well, the pH level was elevated,
and nute lock was beginning to occur.
Flushing can be said to be a very good equalizer to correct problems, it
returns conditions in the soil to a baseline level, which can be
adjusted on the basis of being "empty" of nutrients.
It's important to note that once the pot has been flushed properly,
there will be NO nutrients left in the soil, so after flushing you must
replace the nutrients for the plant to have anything to grow on.
Let the pot dry out some until the soil pulls away from the sides of
the pot slightly before you water next, and apply flull strength all
purpose fertillizer (20/20/20) so there will be no hesitation in the
plants growth due to a sudden lack of nutes.
If you do not do this, the plants will start to slowly turn pale
green, then yellow as the N is depleted and chlorosis takes hold. The
plant will starve to death, and fail within weeks.