Flushing ....

[Taipan]

I have noticed that people talk about flushing their plants regularly with fresh water, and it seems to be offered as a "fix-it" for a lot of peoples problems. I have been growing hydroponically since 1976 and I worked in the Hydroponics industry for 15 years, so I am not just pulling this advice out of nowhere. Do not think that a hydroponic system for indoors is any different to a hydroponic system for outdoors, hydroponics is hydroponics and the people to learn from are the growers who grow multi million dollar crops for a living. If you look at what commercial growers do worldwide you will find that they do not flush their plants with fresh water. It stresses them. If you insist on flushing your plants you flush them with a weak nutrient solution.

 

The reason to flush a plant is to avoid a build up of some of the mineral elements to toxic levels in your growing medium. If you maintain your nutrients at the correct strength you should never need to flush the plants in such a short term crop as MJ. I think most people feed their plants nutrients that are way too strong, they do not need strong nutrients. It is so tempting to give them a bit more of this and that, but if in doubt give them less. If you are growing indoors, they do not need high strength nutrients. My early years of indoor growing involved full strength nutrients, daily monitoring and correcting of pH and CF levels and weekly flushing with fresh water too ... and I was always wondering what was causing this problem or that problem. My best crops with the healthiest plants, with no problems at all, were when I grew on low strength nutrients with no flushing.

 

If your plants are suffering from some nutrient problem caused by incorrect pH or CF or anything for that matter, the plants will be much happier if the conditions are corrected over a short term rather than vigorously flushing with water and then putting them back on full strength nutrients to fix the problem.

 

Just my two cents .....

 

EDIT:- I must add I am talking about flushing during grow and flower cycles, not the important final flush.

Edited February 1, 2007 by Taipan

[F420]

I totally agree with your statement. I would only ever suggest flushing during the grow, if you made the nutrient mix too strong in a medium like coco or perlite etc. just to lower the amounts of stored nutrients.

Then a flush is better than having a too rich medium.

 

In the hydro systems I have used which is mainly flood and drain, I only dump the res every 2 weeks and mix up a new batch. I dont put plain water through the system, till the flushing stage before harvest.

I DO recommend flushing at the end of the grow, but under normal growing terms theres no need to flush.

 

One of the problems with using plain water to flush, is the osmosis process. It will actually suck the salts and nutrients out of the plant.

 

what hydroponic systems have youy had experiance with Taipan??

 

[SukonmiSkunk]

ive got to go to work.. but when I get back.. ill set you straight on flushing for hydroponics....

 

just let me say.. tiapan.. I had the upmost respect for you mate, but...I am glad I am not smoking any of your unflushed crap hey... MJ that hasnt been flushed at all through the grow process will almost EVERY time have serious issues... flushing through the grow.. prevents EVERY issue you will EVER come across... its more of a preventive measure than anything.. but regular flushing.. once a week.. then mixing a fresh batch of nutes will give the plant a growth spurt every time... plants take nutrients.. and they also expell nutrients(ie shit) like we all do.. ill explain this later as well

 

finally.. UNflushed MJ at the final stages, tastes. and smells.. YES.. like hydro nutes...

 

but like I said I need to be at work... so Ill deal with this bullshit when I get home...

 

Spook.. you amaze me with your aggreance... havent you smoked some of my hydro??? didnt you tell me it was some of the best shit youve ever smoked?? or were you just telling fibs mate??? and yet you still agree??

 

mmmmm

[Taipan]

I dont put plain water through the system, till the flushing stage before harvest.

 

what hydroponic systems have youy had experiance with Taipan??

Thanks for pointing that out Spook, I forgot about the last week before harvest, it is a good idea to feed them fresh water then, to remove excess minerals and improve the flavour of the final product.

 

I have tried most hydroponic systems over the years, NFT, Flood and Drain, Drip systems with many different growing mediums, Aeroponics, DWC and also grown a lot of crops by hand watering them. As far as what is the best? They all have their pros and cons and some varieties may prefer one method over another. Any system can grow to full potential if maintained correctly. I had some of my best results in rockwool slabs with drippers, but also really like Flood and Drain. I don't think it really pays to change systems too much, gaining experience with any system will help the grower improve their growing. My latest grows are larger plants in coco ... hand watered. I am a firm believer of the "Keep It Simple" principal and these crops have been excellent as well.

[Taipan]

so Ill deal with this bullshit when I get home...

I certainly didn't start this post to get into a flame war. I am not saying I know it all, but I have worked with many growers over the years, some of these growers are that big they wouldn't dare join a forum and talk about their grow rooms, they have too much to lose. Commercial growing of any plant is a life long learning experience. Some of us are willing to learn, some think they already know it all.

 

I am not going to argue with what you believe, I am well and truly past that. You believe what you want, and advise people how you see fit, and I'll do the same. If you want to test my advice, try some side by side tests, not just for one crop, you need to do it with a few plants and for a few crops for any trial to show true results. Run one system with nutrients at CF 10-12 for the whole crop, no flushing (except the last week). I have done this sort of trialing many times.

Edited January 31, 2007 by Taipan

[F420]

Spook.. you amaze me with your aggreance... havent you smoked some of my hydro??? didnt you tell me it was some of the best shit youve ever smoked?? or were you just telling fibs mate??? and yet you still agree??

 

Yes I have had your hydro buds, and I still say they are some of the best grown buds that I have ever smoked. The flush at the end of the grow is VERY important for a decent taste and smoke.

However flushing an inert medium during the grow is only any good if your system has built up salts. Which inert mediums dont have an issue with.

 

I used to change my res to plain water and run this for a few days, then dump and refill with a fresh nutrient mix. However this didnt do jack shit for the plants, they still grew the same and didnt have many issues.

Salts and toxins will only build up in a non-inert medium, or one that doesnt have the res completely changed every 2 weeks.

Think about it this way, my system I was using was flood and drain, using hydroclayballs (inert).

If I change the res every 2 weeks, for fresh nutrient mix. What is there to benefit the plants by doing a flush?

The medium doesnt hold many nutrients/toxins so thats not an issue, the system doesnt hold toxins/nutrients. So what are you actually flushing for, whats the point??

 

Now as I said, soil, coco or any medium that holds nutrients/toxins is better off with the flush during the grow. As it prevents the toxic build up, and also cleans the medium so that it has the right amount of nutrients and ph level.

 

There was some pretty decent grows around, where they didnt even change the res. They just kept topping it up. Their plants looked ok to me, but I strictly change my whole res every 2 weeks.

 

I always say that there is no right or wrong way. If something works the way you have been doing it, then stick to it. if your plants are happier with the flush, then by all means flush.

But After a number of years, and playing with the different ways and theories etc. I have realised for myself, that in MY grows, done my way. Flushing during the grows serves no purpose.

 

One of the first things I was taught when I first started growing hydro was that. If it works for you, then stick with it. If your plants have problems, then do a flush and see if it helps. I dont have many issues with my plants, So it may be why iIt doesnt appear to be anything positive for the plants.

 

The downside to flushing, is that your overwatering the plants. This can only be a negative thing for the plants IMO.

 

 

ps- Im not growing at the moment, but im planning on running a Power Grower drip system.

[pipeman]

flushing during grow can be to correct a problem, but it can also be a necessary procedure due to the specific hydroponic system you are running.

 

for example in a non recirculating DWC system, where you only have the tubs connected via the bottom, you will tend to get a salt buildup around the netpot, because they are never top watered. So a "flush" once every week or two (basically pouring water through the top of the netpots) to get rid of this buildup will help prevent this problem. also, some growers believe they get greater yields by running their nutes at higher levels and flushing periodically rather than running their nutes at lower levels and not having to flush at all until harvest. its a matter of personal prefereance and trial and error obviously.

 

flushing may also depend on the purity of the water you are using. In matters little in run to waste systems. but for recirculating systems it becomes more necessary to flush at regular intervels because you will tend to get a buildup of unusable salts in the nutrient mix if you use tap water but the same system may not need a water change at all if you were using RO filtered water or rainwater.

 

other reasons flushing may be used is if you've used an additive that is required to be flushed out of your plants medium, like scarid fly drench or some specific bloom booster like canna pk13/14.

 

also remember that "flushing" can mean different things to different people. for some it just means a complete water change, for others it means running straight PH adjusted water through your system for a number of hours, then dumping that before you add the new nutrient mix.

[smoke p]

is it a good this 2 do it ur water gets really bad in ur hyro system?

[moKing]

I going to have to give this a try. Running a recirculating drip system however, i think I'll still have to flush the bucket under the pot with fresh water and hydrogyn peroxide before dumping nutes (each 2 weeks).

I like the tip to use a weak nutrient if flushing is nesecary, I have wondered if this would be better myself.

 

Thanks for the advice

 

 

moKing

[Frazz]

Yea this is all very well if people were aware of the exact EC level of nutrients required by MJ ... but they are not !

... so they follow recomedations made by companies such as CANNA who advise EC 1.8-2.7 which of course is way over the top IMO

 

You see, even though you may have eons of practical experience, people in general will still forgo your advice cause they think some crowd like Canna from Holland may know more than you

whereas in reality Canna and friends do encourage folks to use thier nutes as quick as possible so they will buy more, i think its called marketing

 

So in the long run many people find they have to flush out the toxic build-up due to overfeeding

 

These are my thoughts on the subject , but really all i know about hydroponics could prolly be written on a Tally-Ho paper