coco is a really good hydro medium. you can put seeds/seedlings/clones, right into it and start growing. i keep the ph at 5.8 from start to finish. i "always" allow 10-15% run-off. the reason for run-off is to keep nutes from accumulating in the coco. every time you feed, you're in essence doing a flush. coco is best used with run to waste. that means 100% availability to all required nutes, all the time. no other grow method accomplishes this. some folks recirculate from a rez, but i think you get better results with run to waste. early on i feed once a day. but once the plant gets established, i feed 2 times a day. i hand water, but i've read that coco responds better to numerous small feedings. you do not want your coco drying up! to properly check ph, you take samples of coco from the root-zone, not bychecking run-off. here' some info. from "integral hydroponics."
COCO COIR
is a product derived from the husks of the coconut.
Visually it looks like peat.
It's air capacity is about 30%.
Coir is most suited as a run to waste medium.
Coir can become saturated and it is not truly inert medium.
This means that the nutrient will change over a short period (due to the nutrient collecting micro and macro elements as it passes through the coir.
Coir tends to release potassium and to withold calcium.
For this reason it is desirable to use a nutrient that is blended specifically for coir.
Coir has a remarkable capacity to protect the plants root system in times of heat.
It also tends to promote vigorous and healthy root development.
Plant growth tends to be very consistant with coir.
Coir is very tolerant of over and under watering, which makes it a very forgiving growing medium.
Coir has a very strong cation exchange ability, which means it can hold and release nutrient elements based on the plants needs.
Coir tends to retain nutrient salts. because of this, less nutrient (lower ec) is required.
On a less positive note, coir can also contain high levels of sodium (salt)....
If your growing in coir be aware that this can be a potential problem.
Either purchase a pre-flushed coir product or flush ph (5.5-6.0) stabilised water through the coir prior to use.
Measure the ec of the water and then measure the ec of the run off.
When they are the same, it is ready for use.
Large amounts of potassium are naturally present in coir.
Potassium competes with calcium and magnesium... buffering and plant nutrition needs to compensate for this!!
For this reason there are several nutrients that are specifically formulated with the coco coir's unique characteristics in mind.
By using a nutrient specifically formulated for the coir based system, you are ensuring that your plants are receiving the best possible nutritient package.
