Perlite in soil in fabric pots?

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BigBlonde

BigBlonde

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I am wondering if perlite is a recommended addition to the soil in fabric pots. If so, how much to use?

This is about me thinking ahead to my next grow. I'm planning to use Fox Farm Happy Frog soil in 7-gallon fabric pots. The pots will be elevated by trivets that allow the pots to drain directly downward into saucers. So that means the bottoms will be similar to the sides regarding drainage and gas exchange.
 
Aqua Man

Aqua Man

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I am wondering if perlite is a recommended addition to the soil in fabric pots. If so, how much to use?

This is about me thinking ahead to my next grow. I'm planning to use Fox Farm Happy Frog soil in 7-gallon fabric pots. The pots will be elevated by trivets that allow the pots to drain directly downward into saucers. So that means the bottoms will be similar to the sides regarding drainage and gas exchange.
I think so. I think you can get away with 30-50% the more you add the sooner you will need to feed nutrients and faster they will dry out… which i see as a benefit
 
TSD

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I'm confused @Aqua Man In fox farm you shouldn't have any runoff right?
In theory lol... I always let some run off happen just so I know they are saturated, not a ton, just till it starts dripping steadily, and then I usually pour it back in another one that's not soaked yet or let it suck back up if it will, then tilt it to move the water table a little to make sure its done dripping, then put it back without the saucer onto metal cooling racks that are on a shoe mat to catch rogue drips... and in fabric pots if they get too dry, you basically get immediate runoff... so a saucer is a good plan, and airflow underneath is always a good thing. I usually do about 1/3 perlite in my soil regardless of the kind of pot or if it's in the ground.
 
Aqua Man

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In theory lol... I always let some run off happen just so I know they are saturated, not a ton, just till it starts dripping steadily, and then I usually pour it back in another one that's not soaked yet or let it suck back up if it will, then tilt it to move the water table a little to make sure its done dripping, then put it back without the saucer onto metal cooling racks that are on a shoe mat to catch rogue drips... and in fabric pots if they get too dry, you basically get immediate runoff... so a saucer is a good plan, and airflow underneath is always a good thing. I usually do about 1/3 perlite in my soil regardless of the kind of pot or if it's in the ground.
Yup this ^^^ i mean there is not absolutes in cannabis really. But in the grand scheme you dont want to s of runoff unless your trying to flush something out. It wont harm the plants but it will wash away available nutrients and imo thats just wasteful
 
TSD

TSD

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In theory lol... I always let some run off happen just so I know they are saturated, not a ton, just till it starts dripping steadily, and then I usually pour it back in another one that's not soaked yet or let it suck back up if it will, then tilt it to move the water table a little to make sure its done dripping, then put it back without the saucer onto metal cooling racks that are on a shoe mat to catch rogue drips... and in fabric pots if they get too dry, you basically get immediate runoff... so a saucer is a good plan, and airflow underneath is always a good thing. I usually do about 1/3 perlite in my soil regardless of the kind of pot or if it's in the ground.
That's just my neurotic way of doing things when they're in pots🤣... mine go outside so obviously you need a set up that doesn't require moving saucers in shit if you're staying indoors... which sounds like op has a plan.
 
BigBlonde

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Thanks everyone for sharing your thoughts.

My first grow was my first use of fabric pots. So far, I like them. I began with the pots sitting directly on plastic trays so there wasn't any aeration or runoff through the bottom of the pot. Much of the runoff was absorbed through the sides of the pot. Thus the plants had wet feet.

For my second grow, I'm planning to elevate the pots on trivets, which should improve aeration and prevent uptake of runoff water. This should make the bottoms of the pots drier. Apparently, mixing perlite with the soil would further increase the dryness. That's why I asked about it in this thread. I'm wondering if that's too much dryness. Or is it just what these plants need.

Even though grow #1 is only in its fourth week since the flip, I am preparing my pots for grow #2. I'm thinking about 20% mix of medium-grade perlite would be a good start. I understand more frequent watering may be necessary, and that's okay. I'll also be using smaller pots for grow #2. I'm changing from 10 gallon to 7 gallon pots. I changed grow #1 to trivets and saucers a few weeks ago and have been suctioning up the runoff water, logging the amount and using it again. I've read that a small amount of runoff is good for these plants. They seem to like the change.
 
Buzzzz

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I am wondering if perlite is a recommended addition to the soil in fabric pots. If so, how much to use?

This is about me thinking ahead to my next grow. I'm planning to use Fox Farm Happy Frog soil in 7-gallon fabric pots. The pots will be elevated by trivets that allow the pots to drain directly downward into saucers. So that means the bottoms will be similar to the sides regarding drainage and gas exchange.
I line the bottom with straight perlite then mix 70/30 soil,promix etc. I do it until the mix easily separates when I clump it. The more air space the better in any container,that's why hydroponics works so well. It also makes overwatering less likely,yet still lets the plant anchor.
 
Nesta028

Nesta028

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I run promix HP in 5 gal fabric and tried to go light on perlite early in my current grow. It was a mistake. Even in fabric they held to much moisture. Went to 25% perlite and saw a drastic improvement in plant vigor. Yes you have to water more, but im with @Aqua Man. Thats a good thing.
 
GasFactory

GasFactory

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I am wondering if perlite is a recommended addition to the soil in fabric pots. If so, how much to use?

This is about me thinking ahead to my next grow. I'm planning to use Fox Farm Happy Frog soil in 7-gallon fabric pots. The pots will be elevated by trivets that allow the pots to drain directly downward into saucers. So that means the bottoms will be similar to the sides regarding drainage and gas exchange.
i would not use perlite.. use rice hulls or pumice/lava rock instead or best imo is a combination of both. Pumice is the best but hard to source, i prefer the rice hulls and rocks over perlite. but something is better than nothing.
 
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MIGrampaUSA

MIGrampaUSA

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Thanks everyone for sharing your thoughts.

My first grow was my first use of fabric pots. So far, I like them. I began with the pots sitting directly on plastic trays so there wasn't any aeration or runoff through the bottom of the pot. Much of the runoff was absorbed through the sides of the pot. Thus the plants had wet feet.

For my second grow, I'm planning to elevate the pots on trivets, which should improve aeration and prevent uptake of runoff water. This should make the bottoms of the pots drier. Apparently, mixing perlite with the soil would further increase the dryness. That's why I asked about it in this thread. I'm wondering if that's too much dryness. Or is it just what these plants need.

Even though grow #1 is only in its fourth week since the flip, I am preparing my pots for grow #2. I'm thinking about 20% mix of medium-grade perlite would be a good start. I understand more frequent watering may be necessary, and that's okay. I'll also be using smaller pots for grow #2. I'm changing from 10 gallon to 7 gallon pots. I changed grow #1 to trivets and saucers a few weeks ago and have been suctioning up the runoff water, logging the amount and using it again. I've read that a small amount of runoff is good for these plants. They seem to like the change.
I place mine on what they call plant elevators, which are then put in the saucers. They are always elevated. I took it one step further though at my wife's request ... indoor plants are on casters so she can move them easily without lifting them. A back injury has her under a permanent weight restriction limiting how much she should lift. It's worth considering for anyone who suffers from a back injury ... or if you simply want to make moving them easy.

Edit: I forgot to say I add course perlite and some vermiculite. The vermiculite improves cation exchange which helps in nutrient uptake.
 
BigBlonde

BigBlonde

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i would not use perlite.. use rice hulls or pumice/lava rock instead or best imo is a combination of both. Pumice is the best but hard to source, i prefer the rice hulls and rocks over perlite. but something is better than nothing.
I didn't know about rice hulls when I began this thread. I prefer organic methods, so I ordered some and it should arrive next week. I have used huegelkultr with success in my other gardening endeavors, but some folks don't recommend it for cannabis. Rice hulls seem similar because they decompose, which is a positive for the organic grower, I believe.

This is in preparation for my next grow. The current crop is at flip+30.
 
BigBlonde

BigBlonde

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I place mine on what they call plant elevators, which are then put in the saucers. They are always elevated. I took it one step further though at my wife's request ... indoor plants are on casters so she can move them easily without lifting them. A back injury has her under a permanent weight restriction limiting how much she should lift. It's worth considering for anyone who suffers from a back injury ... or if you simply want to make moving them easy.

Edit: I forgot to say I add course perlite and some vermiculite. The vermiculite improves cation exchange which helps in nutrient uptake.
I didn't begin this grow with elevators and saucers. I'm using them now. I ordered them for my next grow, but decided I could start using them for this grow. I like how the bottom of the fabric pot is also exposed to the atmosphere. Some say it's okay to let the pots sit in runoff water, but I suspect that might not be a good thing due to root rot possibility and less oxygen uptake. This is how I came to ask the question about perlite. I was wondering if there could be too much drainage. Apparently not.
 
Oldchucky

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There certainly can be if you are in a hot dry climate. Unfortunately I can testify to that! L O L
 
R

ritoMox

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I didn't begin this grow with elevators and saucers. I'm using them now. I ordered them for my next grow, but decided I could start using them for this grow. I like how the bottom of the fabric pot is also exposed to the atmosphere. Some say it's okay to let the pots sit in runoff water, but I suspect that might not be a good thing due to root rot possibility and less oxygen uptake. This is how I came to ask the question about perlite. I was wondering if there could be too much drainage. Apparently not.
The Rev wrote an interesting article over at Skunk called Micropond growing.

 
BigBlonde

BigBlonde

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The Rev wrote an interesting article over at Skunk called Micropond growing.
This reminds me of bottom watering. I started with my plants sitting on trays and letting the runoff be reabsorbed into the pot. They seemed to do okay, as in, they didn't die. I suspect the size of the pot would matter when reabsorption is involved.
 
MIGrampaUSA

MIGrampaUSA

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This reminds me of bottom watering. I started with my plants sitting on trays and letting the runoff be reabsorbed into the pot. They seemed to do okay, as in, they didn't die. I suspect the size of the pot would matter when reabsorption is involved.
It's a technique that usually doesn't lend well to cannabis over a whole grow. Your ladies prefer to keep their legs drier between feedings than sitting in water all the time.

It has its place sometimes with seedlings though. You want the tap root to grow down but it won't grow through dry soil. You don't want to over-water either ... It can be used as a technique help a plant get going. Water as normal when you start your seedling. Next watering after the top soil has dried back a bit, sit the pot in about an inch of water long enough for it to absorb into the cup. Place on rack or plant elevator to allow excess to drain properly. You should only have to do this once if at all to get them going. It's a handy trick to prevent dry spots in the soil which is most likely going occur at the beginning of the grow with inexperienced growers trying hard not to over-water.
 
MIGrampaUSA

MIGrampaUSA

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ps perlite is organic and what's the reason for advocating against using it?
I use perlite. I can't really say I know anyone who doesn't since most mixes usually already have at least a bit in it. Perlite is a wonderful thing. It allows the pot to dry out quicker and helps avoid watering issues. Which in turn allows you to water more often with less issues.
 
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