Finishing the Buds

[The Fan]

when i grew with soil, i used to, on recommendation, run my plants through with lots of nutrient free water about 2 weeks to 10 days before harvest to clean any "nutrient taste" out of them. now that i'm growing hydroponically, using organic nutrients, should i give them only fresh water without nutrients for the last 10 days or so? since there is no soil, do i need to keep feeding them nutrients of some kind to keep them healthy in the final run up?

The Fan

 

[Akornpatch]

I think hydro's where the "flushing" concept came from in the first place...so yeah flush before harvest.

 

[Stix]

yeah, you should flush. I recommend flushing for 7 days before harvest. I usually change the water every day if not every other day during those seven days. I would also recommend using a flush solution on the 3rd day of flushing.

 

[Racefan]

You don't want to give them just plain water in hydro. It can shock them and hurt yield. Reduce your nutrient strength to about 1/4 of normal but never go to just plain water. By reducing the amount of nutrient the plant has to use its reserves.

 

[Stix]

How does using plain water in the last week of flowering hurt yield? I really didn't think there was much bud growth in the last week of flowering. Rather its basically the buds ripening. I've actually used flushing solution that is suppose to remove all traces of nutrient in the water as well as straight PH balanced water. Your saying this may shock the plant? I've never heard of this, I was always under the impression you wanna use plain water to eliminate ALL traces of nutrient right before harvest. By no means am I saying I'm right and your wrong. I'm by no means an expert. This is just how I thought you were suppose to flush with hydroponics. Any more info on the subject would be appreciated.

 

[Racefan]

Well I'll tell you what...you all of a sudden go without food or nutrient after having gotten used to a full belly. Tell me you won't experience hunger and be shocked in a way? lol It's the same with a plant. I can't tell you where I learned this from. It's just something I was told by one great grower or another over the last 15+ years and made sense to me. Let me try to get my point across. The last 2 to 3 weeks of a plants life are super important. the buds do most of their filling out in this period and it's always confused me as to why a lot of hydro growers want to deprive their plants of all readily available food. This food is converted to energy to build these buds. By forcing it to use all reserves does eliminate any excess nutrient but IMO 2 weeks of this is too much. IMO 7 days max and only the last 3 day with plain water if you must. The first 4 days should have a little nutrient so the plant doesn't experience hunger and stress. It needs food and energy to build bud. If a person has done things right over the previous few weeks there shouldn't be a lot of "excess" nutrient that requires a long flush to begin with. If so there may be a over feeding or drainage problem.
After sitting here thinking about this for a few minutes I guess flush does depend a little on what type of nutrient is used too but still, no food for 2 weeks is a little much IMO. Outdoor in-ground growers can't flush yet they don't experience a nutrient taste in the bud. Why do indoor growers have these problems?

 

[RangerDanger]

I've grown dozens of crops in ebb n flo hydro, and I've ALWAYS gone the last 10 days without anything but pH-corrected water.
I drain the res., then use a hose to run approx. 1/2 gal/water through each 6" net pot.
Then I re-drain the res. and fill with plain water.
Doesn't shock the plants atall.

During flowering plants use up the nutrients stored in their leaves, which is why they yellow wither and die off as the buds get fatter.

I also grow outdoors in well-drained soil and during the last 10-14 days I give them plain water (*with a bit of unsweetened pineapple juice added to feed the mychorrizae).

 

[The Fan]

Thanks for all the replies. i'm going to use a bit of a mix of all the advice and see how it goes. i'm right now exactly 10 days out. i'm gonna cut the nutrient way down for the next few days and add only fresh water to the resevoir until 3 days out, when i will rinse the pots and use only fresh water in the resevoir. i can tell you this: i've grown in soil for about 5 years with this same strain (skunk) and this is my first hydro batch. it is already bigger, better and sweeter looking than my best soil grown crop. i'm never looking back.

The Fan

 

[Akornpatch]

Ranger...Not sure why, but reading your post,a nd visualizing your grow made my mouth water.

 

[ntezbngggreen]

When flushing I prefer using water that has been "purified" through reverse osmosis. This"soft" water is more soluble for the elements which make up your fertilizer. A little more involved but I find it results in a quicker and more comprehensive cleansing.

 

[channeltrack]

I've been running a test the last month regarding flushing and the effects on the quality of the smoke.
I decided to question the standard response on the importance of flushing after I read numerous hydroponics articles from the commercial world [i.e. lettuce, strawberries, tomatoes etc] that stated that flushing was not needed [and offered biological evidence of why (I have over 7 years experience doing research in the biosciences including botany and it all seemed to make sense from my initial checks).

My test was as follows
Strain - Master Kush [sourced from Buy Dutch Seeds]
Nutrient tank 1 - Standard non organic fertilizer similar to that used for commercial hydroponics farming crops
Nutrient tank 2 - Certified Organic fertilizer

CF was standardised for both tanks at 20 [+/- 4 depending on factors such as evaporation, refill etc] (please note that the NPK ratios differed due to different formulations of the fertilizers)

Buds were removed from each from week 5 - 8 and dried and smoked in a blind test by a group of experienced smokers [8 years or more], this was controlled against a flushed harvest.
Buds were smoked through both an ice cooled bong or in a joint to compare and contrast differences

Results were as follows
taste test
No significant difference noted [i.e. no noticeable bad taste with the inorganic ferts compared to the organic (slight difference in smell though but not able to be determined on blind test which was organic or inorganic by the test subjects)

Effects
No significant effect difference between organic and non-organic non flushed [although it was felt that the one that turned out to be non-organic was slightly stronger]
There appeared to be no difference in come down effects, between any of the test crops. That is, no 'chemical headache' in any of the crops [yes including non-flushed non-organic]

the conclusion from these test is that flushing seems to make no difference to taste and effect in master kush and that there is no significantly discernable difference between organic and non-organic nutes [in the 2 cases so far tried - I will be carrying out a test with the canna range in the few 2 months].

So,
Has anyone else done any tests regarding the effects of flushing or not?

Has anyone tried this with a strain other than Master Kush?

I imagine we have all smoked crops that have given a 'nasty chemical' taste and the headache with it.

Does anyone know of any studies carried out regarding whether this is due to particular strain rather than nutrition regime [in that I have grown strains before that have given the headache / yuck etc feel].

Any opinions / ideas / similar tests appreciated

channeltrack