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Jacks classic 10-30-20, how much to use?

J-Icky

Active member
Ok I’ll start by saying I’m on my first coco grow and everything has been going good.
I use megacrop with some extra calmag and fulvic acid every so often.
I just flipped my plants to flower and they immediately started to look like they may need a little bit more N for the stretch. So I have this container of jacks classic bloom booster 10-30-20. I figure it should give the slightly more N the plants seem to need without having to add all the unnecessary calmag.
My issue is that it says to use only 1/4 tsp/ gal which is 1 gram/gal. This just seems weak to me and even looks very dilute and I certainly don’t want to starve my plants at this critical time. Also I don’t have an EC/PPM/TDS meter, getting the wife to let me buy a ph pen as battle enough lol.

So has anyone ever used this jacks classic bloom booster 10-30-20 in coco(I can only find a few references on this site and they are all soil) and should I be ok if I doubled the dose (jacks recommended 1/2tsp for feedings every 10 days but only 1/4 for every feeding) so instead of 1gram or 1/4 tsp, bumping it to 2grams a gal? Or is there another amount that has proven effective.
I honestly onlynplan to use it til thebplant stops stretching and starts stacking3-4 weeks tops.

Almost forgot to mention that while using the jacks I obviously plan on stopping the megacrop and will only use calmag if it looks like it needs it. I honesty only use it once a week just to make sure there is plenty for the coco to hold onto. Fulvic will also be used every third day.
 
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MJPassion

Observer
ICMag Donor
Veteran
Jack's as a company has been studying cannabis growth using their products for over 10 years.
IMO, your best answer will come directly from Jack's scientists.
:tiphat:
Also, I'm pretty sure that the directions they've given will be repeated.


If you don't want contact with Jacks, go see what you can find on their website.
 

eric2028

Well-known member
Veteran
I’ve ran it at 2.7 grams/ gallon. Per jr peters they recommended as high as 5.66 grams/ gallon. I never went that high. Keep it mind it doesn’t have any calcium in it, they only recommended the first 2 weeks of flower. I switched to mkp around week 2-3 and really like it with jacks 2 part.
 

J-Icky

Active member
Thanks for the replies and I don’t know why I didn’t think to contact them, seems so obvious now that you’ve said it lol.

2.7 seems like it may be more on point than the1/4 tsp, but can’t say I’d be brave enough to try 5, let alone 5.66.

I did find a pic of a feeding schedule for jacks bloom booster and according to the math they sure do recommend over 5. But that schedule is for 25gllon batches and also includes a half rate.

Hopefully they respond in the next couple of days and I’ll let everyone here know what they say.
 

MJPassion

Observer
ICMag Donor
Veteran
I like to watch the cannabis pics flash by on their home screen. :biggrin:


Glad you got into contact with them.
 

sethimus

Member
old formula megacrop only needs epsom salt and and a pk product like mpk, increase base if they look pale
new formula not, just increase the amount if they look pale
 

Hydro8

Member
In general you should always stick to the manufactures instructions and recommendations. Quality and reputable products like Jacks have teams of professionals calculating these instructions - asking questions on the internet has teams of armchair peanut gallery recommendations on how they are smarter then the entire world.

Products like Jacks are designed for professional use and mixing up reservoirs in the hundreds of gallons. When used for small batches the amounts may seem small, but concentrated professional grade chemicals usually go a long way...

PPM meters are inexpensive $10-$12usd, they will tell you just how strong your mix is. I would highly recommend one.
 

J-Icky

Active member
Well I’ve emailed them and have yet to receive an answer, even resent it this morning in case maybe they just missed the first, oh well.

In other news I have gave my plants 2.5grams/gal and haven’t noticed any I’ll effects. I also haven’t noticed anything new or different either. They have just kept chugging along just nicely.
Oh and I also have caught an issue with my original weights. 1/4tsp is actually 1.2-1.3grams not just 1 gram and 1tsp is 5 grams not 4. So if anyone was using my original numbers they may want to back off, or if they are doing fine at least they will know what dose they are actually using.
 

J-Icky

Active member
Well it’s been 2 weeks and I haven’t gotten a response from jacks, not even an auto reply. I sent the email 3 separate times just to make sure they received it.

Regardless like I said in my previous post I was using it at 2.5grams/gal just fine. I have since switched back to using mega crop with MKP since the plants don’t need the extra N at this point. I’m actually a few days from switching back to just plain megacrop and then slowly dropping the dose over the course of 2 weeks before I do a final 1 week flush.
 

J-Icky

Active member
Well I’ll be darned lol, I thinknjacks may be reading these forums. Not 5 min after the last post did I finally receive an email.

So what they recommended for coco was a whopping 8grams/gal. Not sure I’d be comfortable using it that high cause like I said I was using 2.5 and the plants weren’t showing any deficiencies. But for those more daring and with the plants to spare feel free to give it a go.
 

pecor

New member
I'd Stick with Mega Crop and the PK boost. I am seriously impressed with it! I have used jacks in the past, G&N and Botanicare CNS series. Were just killing it with Mega.
 

J-Icky

Active member
MC is my primary nute, I actually only used the Jacks in the week before flower and the first 2 weeks of flower to give it a N boost since it has a bit more N than MC. It also gave the plants the boost in P they need in early flower.

In the future MC will continue to be my primary nute and I’ll use the Jacks the week before I flip and the first week of flowering for the N. After that it’ll be the MC with MKP for weeks 2-4. Then weeks 5-flush I will use a reduced dose of MC with potassium sulfate to reduce the amount of N the plants get in late flowering while still giving the the K they need in that time period.

Oh and I add calmag during veg and the first 2 weeks of flower twice a week. It serves a few purposes for me. It boosts the N, it also obviously gives the plants a bit more cal and mag and also makes sure the coco stays charged with cal and mag and doesn’t become over charged with potassium. Obviously in flower I try to avoid and even lessen the amount of N and also after the 4th week of flower most plants prefer a boost of K and need very little P. So if the soil loses the cal and mag charges and becomes loaded with K, that’s the best time for it to happen as the plants become K hungry and in a way keeps the coco in check.
 

J-Icky

Active member
I’m honesty very pleased with the results I’m getting from megacrop, calmag, MKP, potash, and ful-humix.
I’m not looking to add anything else to the lineup and the only reason I use the Jacks at all is because it’s what I bought and used for a couple months until I got the megacrop. I know the calmag has calnit in it so not only would it be yet another thing I needed to purchase, but it would also be soemthing I already have and have been using.
 

zombywolf7

New member
Been using 1 tsp/gallon Jack's Bloom for years with no problem in Promix. That would be probably 6-7 grams, so 8 wouldnt be a stretch. Fed 1x per week, plain water in between. Some epsom and you are set. Couldnt be any easier, and inexpensive.
 

J-Icky

Active member
When I used it I used 1/2tsp, gal with calmag and it did excellent . I just happened to get my MC sample at the end of that run and wanted to try it and ended up liking it so much I ordered a kilo of it before they stopped selling it in that quantity.

But I’m also a believer in not putting all your eggs in one basket and bybthat I mean I think every grower should have a second nute option readily available. We all know that all plants are different and what one plant may love another may hate. So having the jacks handy is nice if I run into a strain that’s not so fond of the MC formula.

Heck I may do a side by side with the jacks and MC if I can get my one plant to reveg once it’s finished flowering. I took cutting but the rapid rooters ended up with fungus gnats and their larvae did an excellent job of eating anything rootlike the cuttings tried to produce. Now that I know what I should’ve been feeding them with the jacks I still may find out that I like it better than the MC, who knows lol.
 
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