Run off percent per gallon of soil
- Thread starter Indicolas
- Start date
The runoff is not calculated by the soil, it’s by how much water you add, so you add water until you get about 10% runoff of the water you added. Depending on how dry the soil is, it can absorb different amounts of water.
The usual answer is 10% of the water that goes in will run through the soil and be found in the saucer under the pot. It is supposed to be the same percentage no matter what size of pot is being used. The idea is to pour enough water on the properly moist but not completely dry soil and to stop when 10% runs out the bottom drain holes.
Why 10%? Why not 20%? Is the number because that is what hydroponic growers use to determine that their peat moss, hydroton or clay balls, coco coir, or rockwool is wet enough to stop watering?
If you have read the thread on "how to water a potted plant" which was started by Emilya Green you probably noticed that she used the 10% number for several years. Eventually, though, she started to mention that if the gardener becomes used to how heavy the pot feels when it is wet then they can stop watering when just a very small amount comes out the drain holes.
To complicate it even more there are times when after the watering the soil is still dry or shows signs of having dried out within hours. The gardener has to learn to read the soil so that they recognize that the soil has become so dry that it is hydrophobic and repels the water. The water does not soak in like it should and almost immediately is coming out the drain holes. Root-bound plants, large plants in small pots of soil, and allowing to much time between watering sessions are usually recognized as being common causes for hydrophobic soil.
Hi Indicolas, good question! Just enough to know you've made all the soil wet and useful for the plant was what I was starting to say before SmokingWings hit it on the head!
- Thread starter
- #5
Thanks. When does salt build up become a factor to start flushing. Does run off manage this? I grew some really sour weed recently and trying to figure where I went wrong. I had a terrible faster dry also.
It usually depends on what you are using to fertilize the plants. Usually fertilizers that are liquids that have to be diluted before use will build up excess salts. But fertilizers that still need the micro-organisms to break the nutrients down before the plant can make use of them will take a lot longer to build up the salt levels. And, the salts are not the same salt as what we put on our foods.
Since you are growing in a soil mix of with a good amount of compost in it there is a chance you will not have to worry about salt building up. A big thing is what types of fertilizers are being used.
Fertilizers that are primarily for hydro style growing tend to build up the salts faster than the fertilizers that are considered organic materials that still need time to break down.
No. What you are calling "run off" is a way to determine when the soil or growing medium is wet enough for optimum root and plant growth. If there is a need to clear a salt buildup then a "flush" is what you want to do.
Not sure what you mean by "sour weed". Is this sour weed because of the "terrible faster dry"?
seaofgreen18
Well-Known Member
Howdy well for me the only time i want run off in my soil is when im flushing i got be a 4×8 bed and its a MESS if I wanted to do it that way i should have accommodated for flushing when setting up but for 10% run off for high sodium and nitrates levels and 20% for chlorides yes there's chlorides in soil by testing soil it shows that , otherwise keep soil tension at 80mb which is field capacity or 120mb which is dry ,start getting above that and the soil starts to becomes hydrophobic and sheds off water and doesn't retain it ! But if you do a 10% flush for high sodium or nitrate levels ( for instance) i recommend getting soil wet first to field capacity then flush with 10% min 10 gallons of soil should give 1 gal runoff for a flush otherwise no runoff your just flushing away your nuits especially if you lack organic matter in your soil such as compost plus your drowning everything which creates compaction points and ph pockets in the soil which in turn will create out of rang ph in spots and anaerobic conditions then the fungal pathegeons start and its a vicious cycle. Thats Just what i do and my training not criticizing anyones method on here 
seaofgreen18
Well-Known Member
Id also like to add i dont use any synthetic nutrients my soil Will carry me through a whole round with no other inputs except for fungi and bacteria if i were Flush like some id deplete all my reserves before i REALLY NEED THEM Like in flower CA,MG and especially Phosphorous
seaofgreen18
Well-Known Member
Here's a good example i started these a month and a half ago and notice the pea 
color through out the plants? 2 different cultivars in Happy frog 2 gallon pots (for now) 1 tbs of the amendment mix I use KIS mix ,a qtr cup of My worm castings ,adjust ph to 6.9/7.0 i used AG lime to bring it up and .5 ml of Bio mass plus per gallon of water every week no other inputs and especially no runoff i up potted them from a 1 gal container to a2 gallon just itching to get them in the bed but i to tweek it in yet but won't be long waiting in amendment
color through out the plants? 2 different cultivars in Happy frog 2 gallon pots (for now) 1 tbs of the amendment mix I use KIS mix ,a qtr cup of My worm castings ,adjust ph to 6.9/7.0 i used AG lime to bring it up and .5 ml of Bio mass plus per gallon of water every week no other inputs and especially no runoff i up potted them from a 1 gal container to a2 gallon just itching to get them in the bed but i to tweek it in yet but won't be long waiting in amendment - Thread starter
- #10
I had terrible dry which diminished terps and I did flush and probably loss nutes. But the yield was still potent >24%. I'm going to now feed to the end with double one- time flush the last week. Then a critical drying. I'll sit there if I have to lol. Thanks for your replies. All were helpful from everyone. Working myself past the double green thumb.
- Thread starter
- #11
Fimming at the 7th?Here's a good example i started these a month and a half ago and notice the pea
What is a double one-time flush? Not sure if you mean that you will be using twice as much water to flush the soil. One thing you can do is look up the many threads talking about the differences between flushing soil to get rid of excess fertilizer salt build-ups and doing a flush to clean out the plant so it does not taste as harsh or have strange tastes.
It is pretty much recognized now that trying to flush to change the taste will not work. You are in soil so if there is a need to flush it will be because of salt build-up in the soil. You have not mentioned yet what fertilizers and the doses you have been using for the Fox Farm Ocean Forest soil so it makes it a bit harder to come up with a recommendation on flushing. And a flushing to get rid of excess fertilizer salts takes a lot more water than many of us realize.
How much water did you you use? And most of the time if the soil is healthy the micro-organism population will be back up to normal within a day or two so they will be quickly replacing any nutrients that were washed out.
Most likely the drying method did not work. Maybe you dried too fast? Maybe the buds were not allowed to cure once they dried. Or, maybe the harvest was allowed to keep drying and once the buds get over-dry it will often start to taste harsh. It is almost impossible to get the right amount of moisture back and have the curing get back on track once it has dried more than it is supposed to.
- Thread starter
- #13
FFOF trio nutrients in Ffof. 'Double flush' meaning I'll fill the pot twice with adjusted water. Then go back to feeding after the plant recovers. This happens at then of week 8.
I the harsh taste really points to an improper dry.
Are you following the Fox Farm's latest schedule for the basic trio? The schedule shows when the two times the flushing of excess salts from soil grows should be taking place.
No need to adjust pH of the water if that is what you are talking about. Nor any real need to worry about chlorine. Figure out the volume of soil and then pour 3 times that amount of water through the soil. It will run out the bottom about as fast as it is poured in and will be picking up the excess salts along the way. If the soil organism population drops because of the chlorine or pH they will be breeding so fast that their numbers are back up within a day or two.
It is all in the way it the harvest was dried. Flushing the soil will not have any effect on the taste. The flushing only helps to keep the soil healthy so that the plant keeps growing nicely right up to harvest. It is all in the amount of time to dry and the cure.
If you want to know more about how to do better soil flushing and why to do a flush in the first place you can find all kinds of information and opinions by reading the older threards in the "Soil Growing" and "Frequently Asked Questions" sub-forums. Most of the time just reading the first msg will tell where the topic of the thread is going and whether to read through to the end.
