First time using Pro Mix and I am planning on growing various autoflower strains starting out with some CFL's then moving them to 600W HPS. I have read alot of forums and it seems as though BX holds water better while HP (high Porous) has fantastic drainage abilities. If i were to get the BX i would also have to mix in Dolomite lime, Perlite, and possibly some earth worm castings. If i were to get the HP, maybe some extra perlite, and some Dolomite lime. Is there anything else that could be added to HP? And what do other growers prefer, HP or BX? Thanks!
Pro-Mix HP or Pro-Mix BX?
- Thread starter jman24
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chuck estevez
Well-Known Member
I prefer the Hp, and add growstones. and why would you have to Add lime?
http://www.pthorticulture.com/en/training-center/calcitic-vs-dolomitic-limestone/
I've read HP is preferable for HID grows. The vermiculite prevents it from drying too quickly under the hot lights.
I use 60% HP, 20% perlite and 20% Kellogg Patio Plus potting mix. I add 1-2 Tbsp/gal finely powdered dolomite (not pellets). This mix requires watering every 2-3 days.
I use 60% HP, 20% perlite and 20% Kellogg Patio Plus potting mix. I add 1-2 Tbsp/gal finely powdered dolomite (not pellets). This mix requires watering every 2-3 days.
Nullis
Moderator
As it says, if the pH of the material is 5.5-6.2 and it is safe to assume that it is on the low end of that figure, then it wouldn't hurt to add another tbsp/gal lime and that should prevent the pH from dropping significantly over a longer course if you're basically going to be treating it like soil.
GibbsIt89
Well-Known Member
Promix HP has more perlite in it, this allows it to dry out faster. Promix BX has more vermiculite in it so it holds water longer. It all depends on your grow style. Some people add slow release nutrients in it so they only have to water, thus they would probably prefer the Bx so they do not need to water as often. If you are simply just using the promix as a "dead medium" and adding your own nutes to it with every watering then you would want the HP so that you can get more feeds into your plant. This is what I do, I don't add anything to the soil, I just use straight Promix HP and add my nutrients in with every watering so I can give them what I want and how much. I'm thinking of leaning towards the slow release, then the plant can feed itself instead me over feeding it or wasting my nutes but this has worked just fine for me so far.
I don't add cal/mag or lime or castings or any of that. Most nutrients has all of that in it already, add a little PH up or PH down and your good. In soil you want your PH to be 6.0-6.5ish so I just bring my PH to 6.5 then if the soil is a little more acidic say 5.5 it'll balance out around 6. I always check my runoff's PH.
This has done me good for a few years now. I was a little MIA for about 2 years from this website, since I've came back, all I hear about is cal/mag this cal/mag that... its just another thing they get you to buy to add to your plants. If your plants actually need it, they will tell you. There is already calcium and magnesium in most base nutrient brands. If you are making an organic mix/soil mix that you would just like to water once in awhile then sure, find a nice recipe, ask around, maybe use the Promix BX instead, add all your cool shit in, brew a tea, whatever. But if you are just going to do what I am doing and add nutrients out of a bottle every watering then adding stuff to your soil will actually cause you more problems, it is better to not give your plant enough then to overdue it.
I am NO EXPERT here just sharing my experience, hope this helps.
Cheers
I don't add cal/mag or lime or castings or any of that. Most nutrients has all of that in it already, add a little PH up or PH down and your good. In soil you want your PH to be 6.0-6.5ish so I just bring my PH to 6.5 then if the soil is a little more acidic say 5.5 it'll balance out around 6. I always check my runoff's PH.
This has done me good for a few years now. I was a little MIA for about 2 years from this website, since I've came back, all I hear about is cal/mag this cal/mag that... its just another thing they get you to buy to add to your plants. If your plants actually need it, they will tell you. There is already calcium and magnesium in most base nutrient brands. If you are making an organic mix/soil mix that you would just like to water once in awhile then sure, find a nice recipe, ask around, maybe use the Promix BX instead, add all your cool shit in, brew a tea, whatever. But if you are just going to do what I am doing and add nutrients out of a bottle every watering then adding stuff to your soil will actually cause you more problems, it is better to not give your plant enough then to overdue it.
I am NO EXPERT here just sharing my experience, hope this helps.
Cheers
Thanks for the advice! ill definitely have to get the PH up and down. I do plan on adding my own nutes with every watering. Is there a preferable series of nutes that work well with autoflowers? I currently have Fox farm grow big for veg(6-4-4) and Tiger Bloom for flower (2-8-4), will those work? I decided to go with the HP this morning so i could add my own nutes, probably try slow release with next grow.
chuck estevez
Well-Known Member
I use jack's citrus feed, Dyna-gro foliage pro also works well in pro-mix. Both of those ph water to around 6.7 6.8, so i don't even use ph up or down, I occasionally check my ph just to make sure it's good.
GibbsIt89
Well-Known Member
Your good for your first grow man. Don't let people on here tell you that you need this and that. Take baby steps. All you need is a simple 1 or 2 or 3 part base formula. Don't worry about additives, you can experiment with that stuff later. I have never tried foxfarm but I see that brand alot on here with good comments. I actually tried to order them for this round but they don't sell them here in Canada and it'll cost me double to ship it here. Check out my first grow in my signature if you want. I spent way too much money but I sure learnt how to clone and veg really well lol.
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GibbsIt89
Well-Known Member
I forgot to mention. Eventually when I had a grow at my buddies he was in charge of taking care of the plants and everything obviously, I would just pop in once in awhile to check on everything. He was learning too.. funny what happened is I gave him a 2 part base nutrient. One set for flower and one set for bloom. He misplaced part B bloom without realizing and only fed them part A bloom throughout flower, still to this day was the cleanest stankiest kush I've had. It was obviously the strain, was a bagseed so couldn't tell you but just goes to show you really don't need to give your plants much, its a weed, it'll do its thing regardless of your help. We were using promix HP then too, we didn't PH balance that grow either using tap water. After mixing was probably ya close to 7.0 ph so it would balance out in the soil where we needed it.
GibbsIt89
Well-Known Member
And what if you do?
Nullis
Moderator
pH is crucial, in hydroponics.
In soil and potting mix being treated like soil other kinetics are at play. There is the cation exchange capacity of the soil or potting mix materials (humus, sphagnum, coir, vermiculite, perlite which has no CEC); the related buffering capacity of the media; reserve acidity of the soil\materials (e.g. sphagnum); and base cation saturation of the media.
For these reasons and more, you may not be affecting pH as much as you think, your runoff might not be quite as accurate as you think... the very idea that you'd know exactly what pH the plant prefers and just how on 'point' it has to be is a very cunning illusion. You pH the water that goes in, you see the water that comes out is "good", plant is growing well, you pat yourself on the back. Repeat.
Soil, however, was designed to resist changes in pH especially sudden changes. Certain materials, primarily sphagnum which has got to be the most common potting mix ingredient tends to be acidic, has a lot of reserve acidity (H+ adsorbed to particles). Reserve acidity is where active acidity comes from, which is acidity contributed to the soil solution. Lime neutralizes the acidity in the media (and associated solution), both directly and by keeping CE sites filled with Ca and Mg (which are base cations). Since most potting mixes are typically marketed to be suitable for a wide range of plants, or for hydroponics they have been limed just enough to get the pH to 5.5-6 and could thus use more lime.
With quality soil that has good organic matter content, and in certain cases some additional garden or dolomitic lime, there is no need to pH irrigation water and in many cases no need to pH nutrient solutions either. Even if the solution is on the acidic side, the pH of the soil will ultimately balance out.
If you look at a nutrient availability chart you might notice that there is no such thing as a "perfect pH" where everything is available. The charts themselves differ a bit, and the fact of the matter is that different plants tend to prefer growing at various pH ranges which can be more or less narrow. Acid loving plants, e.g. berries, still manage to meet all of their nutrient requirements in fertile soils despite the pH being 4.5 to 5! This is possible because there is much more to soil and nutrient uptake than most anyone could have imagined.
It's a bummer that this has to be explained ever two or three days, it's not the folks who ask the questions that is annoying, it's the constant bum answers that follow. Thanks for Laying the truth down in this one.
GibbsIt89
Well-Known Member
when using promix HP it is preferred to balance your water/nutrients mix to 5.8-6.2 so that it balances out between 6.0-6.5 in the soil someone on here actually called the company and got the info from them.. it is treated like a hydroponic growing medium they said. The person that did this for me also said he asked his hydroshop guy and he said the same thing but said 5.8 for veg and 6.2 for flower apparently.. maybe because of the way the nutrients balance out before PH balancing.. but you get the idea. Cheers
Springtucky
Well-Known Member
I use 7gal pots and use the BX mixed with roots organic. I use a lot of compost teas and organic nutes. Lot less stress over ph than in other methods.
d0rk2dafullest
Well-Known Member
HP for small pots, water everyday. Bx for BIG pots 5gal+ for every OTHER day water.