using a PK additive on its own for a week

[keepleft]

hi ive read someone on here (think it was luke) say that best way to use PK additive is on its own at full strength for a week (Without nutes) at about week 5. then go back to nutes.

 

anyone tried this or can verify this for me?

[Luke Skywalker]

Well, I could!

 

Some advise using all the way through flower, but this can have an unwanted effect on nutrient solution composition, where if it reaches particular strength (ec 2.0+) it can cause precipitation.

 

A PK hit at about 3 weeks before harvest does great things for crops. I'm sure many would advise you other ways too, and strain does come into it a fair bit too. Play around a bit and you may find better methods for your grow and your strain.

 

Actually, might be a good idea to have some discussion about PK usage on the boards... So lets hear from some of you!

 

One side note which I've recently had come up, is that it shouldn't be used in conjunctions

[keepleft]

luke what do u mean by it shouldn't be used in conjunctions?

 

ive added it at full strength with silica today and no nutes. its start of week 6 so may be a week late. but im going to try it on its own without nutes for a few days and see how it goes

 

ur right about it being strain dependent. the previous strain i had could just handle half strenth at 1ml per litre and even at that weak strength it showed yellowing of the leaves straight away. whereas in another grow with the current strain i added it 2 weeks ago (start of week 5) at full strength 2ml per litre and noticed hardly any yellow leaf burn. they buds got heavy as though! so heavy the bloody scrog net collapse!

Edited May 4, 2006 by keepleft

[Tom]

hi ive read someone on here (think it was luke) say that best way to use PK additive is on its own at full strength for a week (Without nutes) at about week 5. then go back to nutes.

 

anyone tried this or can verify this for me?

Yeah, I've done it that way with great results but I got the same results using it as directed. I have also used it at full strength on week 3 and then again at week 5, this did increase the yield quite well but it also extended the flowering cycle by around 2 weeks.

 

[WantDaChronic]

i used pk 13/14 too early and i think it may have been a little strong too, but it prolonged flowering by 8 weeks on an 8 week strain no kidding, they reverted back to vege and i didnt see a preflower for another 6 weeks

 

i used it on my celtic plants later in flowering, week 5 or 6 i think and had great results, so much so that the plants got so top heavy they fell over

 

my advice is to use it once the buds are well formed which is usually 3-4 weeks before harvest and a smaller dose is better than a larger one, well in my experiences anyway

[thc24]

I havnt made up my mind which works better for me, I Found that results where about the same but the earlier you add it the faster plants mature sometimes maturing too fast ie brown pistles yellow leaves when resin isnt Quite ready. Use it like a ripener just as plants look nearly done give them a dose.

 

Go with the bottle directions Mate it works well. My problem is that it worked so well i overdo it like most thing i do.

 

in my last grow where i started weak PK in the 4th week ontop of nute and then PK only for the week before flush. This grow with Pk at 5th week they didnt ripen so fast.

 

My plants finnish in 8/9 weeks with PK its been a while since ive done a grow without so i cant disagree with tom statement on PK taking plants longer to flower..

[keepleft]

i dont like the idea of them taking longer to finish!

 

i added it at the begining of week 6 (a week later than recommended) only because i heard that adding it too early can actually cause them to ripen too quick and therefore prevent them from reaching full potential

 

i was told by a mate at holland forge to add it when the calyx has fully opened, but im not quite sure what he means by that!

 

im interested in more information on precipitation? is that why luke u say its better to add it without nutes for a week? im concerned though that adding it without nutes for a week would cause them to have deficiencies in nitrogen and micro nutrients? and therefore inhibit maximum potential?

[Luke Skywalker]

The plant has adequate reserves of micronutes and nitrogen to tide it over during this period. Some strains will do better with a 5 day application, but most do okay with a seven day usage.

 

Silica additives may be an exception to the rule of "additives other than nutrients are okay" as it is potassium silicate and thus quite open to precipitation. Keep a close eye on your solution and all silica additives should be diluted into the tank before anything else.

[Luke Skywalker]

Oh yeah, if you like, you could apply the silica as a foliar feed for the week of PK only application to help ensure the new growth is well supplied with silica, but avoid any potential precipitation reactions.

 

If it takes longer to mature I feel this would be due to environmental factors rather than PK application. If anything it would encourage earlier ripening than normal. That said, every strain has it's quirks.

[thc24]

Hi lukeSkywalker,

when you say precipitation do you mean in the res or in the pots/roots themselves. At 2.6 ec i dont have any problems but with the pk in in res at over 2.8 i do find a salty build up in filters and a fine sludge on bottom of RES, A good strong mixing pump turned on once or twice a day keeps the nute mixed well most of the time.