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Promix HP....how much perlite to add?

L

Lune TNS

Hello all. Just today I bought some promix hp and perlite. I reallize that the HP has some perlite already mixed in, but the guy at the hydro store reccomended that I still do a 50:50 ratio of PM:perlite. After doing a quick search on these boards, I haven't yet found someone whoo adds this much perlite to the HP. So my question is simple: how much perlite should I add to the promix hp? I don't know whether to trust the hydro store guy, or the people on these boards.

Thanks for the help guys.
 

inflorescence

Active member
Veteran
I've never heard of a 50:50 hp perlite mix in my life.
HP's got a lot already.
Also depends on what size your adding.
The perlite in HP is small to compared say the chunky fox farms.
 
G

Guest

Don't mix it 50/50. That's way too much.

I don't even add any myself but may start.

I don't think you *need* more than a 5-1 ratio. I'm just guessing what my friend mixes his at from what I've seen.
 
I do about 40 percent small perlite to organic soil with no perlite in it. I have to water every 2 to 3 days, and it depends on what your set up is, conditions, you know, temps, It's hotter that hell here in the S.W. U.S., The roots have to oxygenate, thus one of the requirements of airid soil, of course I'm a newb and it works for me.
 
lots of people i know use a 50/50 mix. soil itself is very dense and the perlite lightens it up substantially in this half half mix... similar to using coco. Lots of room and air will result in a great root system.

if ur just starting growing or using soil consider this; noobs to a system usually overwater, and underwater means ur going to have to water more often which means time....... so which side would u rather be on? the underwatering or overwatering? i'd recommend starting with 25% perlite instead of straight soil or instead of a really light 50/50 mix.
 

inflorescence

Active member
Veteran
thedarkknight said:
lots of people i know use a 50/50 mix. soil itself is very dense and the perlite lightens it up substantially in this half half mix... similar to using coco. Lots of room and air will result in a great root system.

if ur just starting growing or using soil consider this; noobs to a system usually overwater, and underwater means ur going to have to water more often which means time....... so which side would u rather be on? the underwatering or overwatering? i'd recommend starting with 25% perlite instead of straight soil or instead of a really light 50/50 mix.

He meant 50% HP and 50% perlite.
HP already has like 30% perlite. It's not "regular" soil by any stretch.
It's not even soil, it's soiless.
 
inflorescence said:
He meant 50% HP and 50% perlite.
HP already has like 30% perlite. It's not "regular" soil by any stretch.
It's not even soil, it's soiless.

so what's ur point?? how does this help the guy?? what would u compare peat moss to? hydroton or rockwool :rolleyes:

hp does not have 30% perlite... more like 15% and it not big enough perlite imo. i know people who use 50/50 coco/perlite... so if that works well, than a 50/50 mix of hp/perlite would work fine... however i dont recomend it. if ur trying soil out for the first time, put a thin layer of perlite at the bottom of your container and just toss the regular hp on top... easy job, use about 10% your total soil height on the bottom. It will travel upwards if wet or u overwater creating air channels, and it'll drain the water from the bottom better. simple... no mixing different bags and u get the benefit of the extra perlite when and where its needed. if u recycle for ur next run, than it'll be mixed for u.
 
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inflorescence

Active member
Veteran
thedarkknight said:
so what's ur point?? how does this help the guy?? what would u compare peat moss to? hydroton or rockwool :rolleyes:

hp does not have 30% perlite... more like 15% and it not big enough perlite imo. i know people who use 50/50 coco/perlite....

My point was hp is not soil or coco (true soil and/or coco have no added perlite), that would be an apples to oranges comparison. HP is a blend with lots of perlite. If you then blend this with 50% more perlite you will have too much perlite, unless your intention is to grow in 65% perlite/35% peat..
It helps the guy becuase he heard to add 50% perlite to his hp. No one adds that much.

Also, you're putting netting to cover your container drain holes right. Otherwise that perlite at the bottom is just gonna wash out.
 
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inflorescence said:
My point was hp is not soil or coco (true soil and/or coco have no added perlite), that would be an apples to oranges comparison. HP is a blend with lots of perlite. If you then blend this with 50% more perlite you will have too much perlite, unless your intention is to grow in 65% perlite/35% peat..
It helps the guy becuase he heard to add 50% perlite to his hp. No one adds that much.

Also, you're putting netting to cover your container drain holes right. Otherwise that perlite at the bottom is just gonna wash out.

fuqin 54646516513 users at this site, and they can't save a message that hasn't been posted!! wtf

Lots of people grow well in a 65/35 mix but your right that woudn't be soil that would be more along hydro

the perlite on the bottom tip was meant as a quick simple help in case of overwatering, which can kill a plant quickly in pure soil and a lot of people go through when first using pure soil.... its not meant for a constant run to waste system. No mixing involved, just pour some perlite, than top with promix whatever or sunshine etc... easy job. As much medium comes out of the drainage holes wether its soil or perlite... try it some time.
 

meduser180056

Active member
IME promix HP is only about 15% perlite. I'd add 30-40% more perlite to that mix.

Cuz like the above said if you don't add enough you can run into issues with overwatering.

I'd rather have em drying out too quick than being overwatered. Overwatered plants turn into runts real quick.
 
G

Guest

I don't add perlite till last, after all amendments. Then I like perlite to be about 20-30%% of the final volume.(using promix which already has some) I like my soils light so they drain really well and have lots of potential air spaces.

Obli
:sasmokin:

There it is.
 

inflorescence

Active member
Veteran
inflorescence said:
HP already has like 30% perlite. It's not "regular" soil by any stretch.
thedarkknight said:
hp does not have 30% perlite... more like 15%
meduser180056 said:
IME promix HP is only about 15% perlite.

http://www.premierhort.com/eProMix/Horticulture/Products/GrowingMediaCat/Regular/fPeatMoss.htm
http://www.premierhort.com/eProMix/Horticulture/Products/GrowingMediaCat/mycorise/fBiostimulant.htm

Avg 70% peat. Since there is nothing else but perlite by volume in this blend that means 30% perlite. :bashhead:

I've only been doing soiless for over 20 years now. lol
 
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there's no way that HP is 30% perlite... volume, weight or anything else. if that's what the company says... then they are wrong lol

20 years of growing wow u must have some great stories to tell.
 
G

Guest

I'll clarify my own remarks a bit.

I do not believe there is an arbitrary amount of perlite one should add to their soil mix. I say 20-30% of my final mix, BUT....if the soil doesn't drain as fast as I want, I'm not afraid to add a little more. If the soil drains too fast( unlikely for me) then I would add back some soil mix.

Perlite, in my opinion, is to provide better drainage and aeration for a soil mix. You add what you need to achieve the soil consistency and drainage you want....whatever that takes. e.g. Some soils high in peat make need more perlite than others with a different type of peat, compost or other materials.

My soils may dry out a little quicker than some folks, but that's OK with me. Weed likes well draining soils, and doesn't mind getting a little dry...and in fact, it prefers to go a lil bit dry.

Obli
:sasmokin:
 

fatburt

Member

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