Re-Use Soil

[Wildbilly]

Hi All,
My first harvest is curing now but for next springs grow I was wondering if I could use the same soil? I used Fox Farms Happy Frog and Ocean Forest in a 50/50 mixture. The only issue I had was with a small amount of caterpillars that I eliminated with an organic spray recommended here.
If so, how should I store it?
Should I leave the root ball in the soil to break down?
Any additives I should add for the next grow?
I had 2 plants growing in two 20-gallon fabric pots, one in a 15-gallon and one in a 10-gallon. Should these be cleaned and sterilized before the next grow? If so, how would you recommend ding that?

Thank you in advance for your help!

 

[garybo]

@Wildbilly , hope your day is going well.

That question about your soil has been tossed around for some time and there is no definitive answer that I have found.

From experience, I've found out that my current medium, which is on my 3rd grow is not performing as well as it had in the past, my nutrient is the same but the plants did not get to the size they have been in the past. I've decide to renew this coming spring, I grow outdoor.

Having said that, there is a product that helps condition the soil, its called Recharge. The manufacture claim's are:

"Use Recharge On Your
Clones / Seeds
Inoculate when first roots are visible with ½ tsp per gallon water / nutrient solution.
Transplants
Water in at ½ tsp per gallon water / nutrient solution to minimize transplant shock.

Vegetative Plants
Use ½ tsp per gallon of water / nutrient solution, once a week.

Flowering Plants
Use ½ tsp per gallon of water/nutrient solution, once a week. Stop two weeks before harvest.
Added Benefits of Using Recharge

1. Prevents Nutrient Burn
Sometimes people overfeed their plants. The beneficial microbes in Recharge help digest any excess nutrients, making your plants less likely to burn.
2. Helps Prevent Root Rot
Bacteria like Bacillus Subtilis surround your root zone making it harder for root rot to take hold. Recharge is packed with this, and similar beneficial microbes.
3. Less Stress Over Pests
Stronger plants means higher brix and more resilient plants. This means your plants are less attractive to mites and other pests. When it's harder for bugs to feed on your plants, they're more likely to go elsewhere.
4. Stops pH Lockout
When your pH levels are out of whack, your plant can experience pH/Nutrient lockout. The microbes in Recharge help regulate pH level at the rhizosphere, making it so your plant can better access the nutrients you're feeding it."

The above description is a cut and past from the manufacturer.

As far as the root ball, that's a good question, I toss mine.

Glad you caught those caterpillars early, they can destroy a plant in short time by embedding their eggs under the plants skin.

Good luck on your upcoming grow.

 

[SmokingWings]

Some interesting questions. The way I see it there is no real right or wrong to the answers. A lot will depend on your circumstances and what you have available and possibly how much room, etc. More of what is convenient or works for you.

If so, how should I store it?

I have metal tubs of various sizes. These can be kept outside all year. If the tub has a hole in the bottom I just fill them up with used soil and let them sit till needed. If the tub does not have any sort of drain holes I will cover them to avoid the soil getting soggy from accumulated rain. Sometimes I mix up a new batch of soil and mark the tubs so I know it is a new mix.

In the basement I have two very large tubs, each holding 35 gallons of soil. I made one lid that fits so I can stack one on top of the other. I use the soil in those for the plants in the grow room and when one tub is empty I will refill it from the pots of used soil that are being stored outside.

Any additives I should add for the next grow?

The ReCharge that @garybo mentions could be used. Or get some more of the Fox Farms soils you mentioned and mix those in. The previous grow did use some of the available nutrients so those have to be replaced but I feel that the plants use a lot less than we often think they did. Up to you but it is a good time to add some amendments that might come in handy later when the plants start to flower. I am thinking along the lines of Kelp, Neem Meal or Crustacean Meal but there are others that some grower like to use.

I had 2 plants growing in two 20-gallon fabric pots, one in a 15-gallon and one in a 10-gallon. Should these be cleaned and sterilized before the next grow? If so, how would you recommend ding that?

Again it is a personal choice depending on how much room you have and how healthy your existing used soil mix is for starters. The nice thing about being able to dump all the soil into one pile is that it is easy to add amendments at the beginning of the off season and let the micro-organisms start to compost those allowing the nutrients to become available when the plant needs them.

Some growers use huge containers and will leave everything in the soil and plant the next seedling just like they would if they were growing in a garden. I am thinking along the lines of the Living Organic Soils.

If you want you can dump the soil into a pile and clean out the pots. I figure it is best to do that outside on a warm day but up to you.

Should I leave the root ball in the soil to break down?

Nature has been doing that since the first forms of plants floated onto a beach and started to grow roots into the sand. Worked well for a couple of billions of years so far.

Leave the roots and a cut off the stem several inches up. Add water if necessary to keep the soil moist but not soaking wet. The roots will decompose, sort of along the lines of what happens with a Living Organic Soil grow. As they decompose they will return those nutrients. It can take a month and maybe up to 2 or 3 but one day you should be able to grab that piece of stem and twist it and it will come free leaving very few roots behind. Often if you then dump the pot of soil you will notice that there are next to no roots left.

If I don't have time or for some reason I need to use the soil right away or before the roots have completely decomposed I will dump the stuff into the large tub and chop it all up with a hand trowel. It all blends together.

My first harvest is curing now but for next springs grow I was wondering if I could use the same soil?

What you do is up to you based on what you have going, available room, and so on.

 

[Wildbilly]

@Wildbilly , hope your day is going well.

That question about your soil has been tossed around for some time and there is no definitive answer that I have found.

From experience, I've found out that my current medium, which is on my 3rd grow is not performing as well as it had in the past, my nutrient is the same but the plants did not get to the size they have been in the past. I've decide to renew this coming spring, I grow outdoor.

Having said that, there is a product that helps condition the soil, its called Recharge. The manufacture claim's are:

"Use Recharge On Your
Clones / Seeds
Inoculate when first roots are visible with ½ tsp per gallon water / nutrient solution.
Transplants
Water in at ½ tsp per gallon water / nutrient solution to minimize transplant shock.

Vegetative Plants
Use ½ tsp per gallon of water / nutrient solution, once a week.

Flowering Plants
Use ½ tsp per gallon of water/nutrient solution, once a week. Stop two weeks before harvest.
Added Benefits of Using Recharge

1. Prevents Nutrient Burn
Sometimes people overfeed their plants. The beneficial microbes in Recharge help digest any excess nutrients, making your plants less likely to burn.
2. Helps Prevent Root Rot
Bacteria like Bacillus Subtilis surround your root zone making it harder for root rot to take hold. Recharge is packed with this, and similar beneficial microbes.
3. Less Stress Over Pests
Stronger plants means higher brix and more resilient plants. This means your plants are less attractive to mites and other pests. When it's harder for bugs to feed on your plants, they're more likely to go elsewhere.
4. Stops pH Lockout
When your pH levels are out of whack, your plant can experience pH/Nutrient lockout. The microbes in Recharge help regulate pH level at the rhizosphere, making it so your plant can better access the nutrients you're feeding it."

The above description is a cut and past from the manufacturer.

As far as the root ball, that's a good question, I toss mine.

Glad you caught those caterpillars early, they can destroy a plant in short time by embedding their eggs under the plants skin.

Good luck on your upcoming grow.

Thanks for the info Garybo and hope all is well!

 

[Wildbilly]

Some interesting questions. The way I see it there is no real right or wrong to the answers. A lot will depend on your circumstances and what you have available and possibly how much room, etc. More of what is convenient or works for you.


I have metal tubs of various sizes. These can be kept outside all year. If the tub has a hole in the bottom I just fill them up with used soil and let them sit till needed. If the tub does not have any sort of drain holes I will cover them to avoid the soil getting soggy from accumulated rain. Sometimes I mix up a new batch of soil and mark the tubs so I know it is a new mix.

In the basement I have two very large tubs, each holding 35 gallons of soil. I made one lid that fits so I can stack one on top of the other. I use the soil in those for the plants in the grow room and when one tub is empty I will refill it from the pots of used soil that are being stored outside.


The ReCharge that @garybo mentions could be used. Or get some more of the Fox Farms soils you mentioned and mix those in. The previous grow did use some of the available nutrients so those have to be replaced but I feel that the plants use a lot less than we often think they did. Up to you but it is a good time to add some amendments that might come in handy later when the plants start to flower. I am thinking along the lines of Kelp, Neem Meal or Crustacean Meal but there are others that some grower like to use.


Again it is a personal choice depending on how much room you have and how healthy your existing used soil mix is for starters. The nice thing about being able to dump all the soil into one pile is that it is easy to add amendments at the beginning of the off season and let the micro-organisms start to compost those allowing the nutrients to become available when the plant needs them.

Some growers use huge containers and will leave everything in the soil and plant the next seedling just like they would if they were growing in a garden. I am thinking along the lines of the Living Organic Soils.

If you want you can dump the soil into a pile and clean out the pots. I figure it is best to do that outside on a warm day but up to you.


Nature has been doing that since the first forms of plants floated onto a beach and started to grow roots into the sand. Worked well for a couple of billions of years so far.

Leave the roots and a cut off the stem several inches up. Add water if necessary to keep the soil moist but not soaking wet. The roots will decompose, sort of along the lines of what happens with a Living Organic Soil grow. As they decompose they will return those nutrients. It can take a month and maybe up to 2 or 3 but one day you should be able to grab that piece of stem and twist it and it will come free leaving very few roots behind. Often if you then dump the pot of soil you will notice that there are next to no roots left.

If I don't have time or for some reason I need to use the soil right away or before the roots have completely decomposed I will dump the stuff into the large tub and chop it all up with a hand trowel. It all blends together.


What you do is up to you based on what you have going, available room, and so on.

Thank you Smoking Wings! Great info!!

 

[SmokingWings]

Should I leave the root ball in the soil to break down?

This occurred to me while reading and participating in another thread. Many growers mix or buy their own soil and have no problem adding Kelp Meal which will then break down in a few weeks. So why worry about the roots left behind from the previous plant?

Something else about leaving the root ball that we can cause us to wonder.

 

[Emilya Green]

Hi All,
My first harvest is curing now but for next springs grow I was wondering if I could use the same soil? I used Fox Farms Happy Frog and Ocean Forest in a 50/50 mixture. The only issue I had was with a small amount of caterpillars that I eliminated with an organic spray recommended here.
If so, how should I store it?
Should I leave the root ball in the soil to break down?
Any additives I should add for the next grow?
I had 2 plants growing in two 20-gallon fabric pots, one in a 15-gallon and one in a 10-gallon. Should these be cleaned and sterilized before the next grow? If so, how would you recommend ding that?

Thank you in advance for your help!

I reuse my soil 5 or 6 times and keep adding in new soil as needed, as it gets lost in the process. I use almost exclusively Fox Farm Ocean Forest. The only place that I use Happy Frog is when starting new plants in solo cups. Happy Frog is mostly sphagnum moss, and after 2 or 3 runs, it will start to break down, and when it does the soil will go acidic and it will be hard to grow cannabis in it. Your 50/50 mix is going to have this problem on your third grow with that soil. As you move into the future, stop mixing 50/50, and use Happy Frog only for what it was designed for, for starting new plants. Ocean Forest is a rich organic soil and it will draw bugs to it between grows. Be sure to use a good systemic insecticide on that soil before the new grow gets going too long, or you are very likely to have fungus gnats and even aphids.

 

[Emilya Green]

regarding the old roots...
I just started a new plant right in the 5 gallon SIP bucket that was just used to harvest a plant. All I did was to grab the main stem and twist, until I was able to pull the central mass of roots out of the middle, and then I planted the new plant right where the old one used to be.

As said above, the old roots will decompose and make room for the new ones. The added benefit is that all of the nutrients, vitamins and such that were a part of the old roots is not lost, nor were the specialized microbes that worked along with those previous roots. All of that goodness is all still in there, ready to help your new roots develop strongly.

 

[732002]

I reuse my soil 5 or 6 times and keep adding in new soil as needed, as it gets lost in the process. I use almost exclusively Fox Farm Ocean Forest. The only place that I use Happy Frog is when starting new plants in solo cups. Happy Frog is mostly sphagnum moss, and after 2 or 3 runs, it will start to break down, and when it does the soil will go acidic and it will be hard to grow cannabis in it. Your 50/50 mix is going to have this problem on your third grow with that soil. As you move into the future, stop mixing 50/50, and use Happy Frog only for what it was designed for, for starting new plants. Ocean Forest is a rich organic soil and it will draw bugs to it between grows. Be sure to use a good systemic insecticide on that soil before the new grow gets going too long, or you are very likely to have fungus gnats and even aphids.

Why don't you add dolomitic lime to control PH and keep reusing the soil?
I have been using peat based soil (sunshine #4 and promix HP) I add lime but have no idea how much or how often is best.

Nutes: Down to Earth 4-4-4, DR Earth Flower Girl 3-9-4 or Alaska morbloom 0-10-10

Bugs: Systemic neem oil for my thrips, it takes time to work so be proactive, mosquito bits for gnats.

 

[Emilya Green]

Why don't you add dolomitic lime to control PH and keep reusing the soil?
I have been using peat based soil (sunshine #4 and promix HP) I add lime but have no idea how much or how often is best.

Nutes: Down to Earth 4-4-4, DR Earth Flower Girl 3-9-4 or Alaska morbloom 0-10-10

Bugs: Systemic neem oil for my thrips, it takes time to work so be proactive, mosquito bits for gnats.

You can and it will work for a while, but eventually the sphagnum Moss will all eventually break down and the soil will go flat, not being able to retain a lot of water.

 

[732002]

With my peat/perlite soil I feel it is the perlite that has broken down, I need to add perlite to increase drainage.

 

[Nunyabiz]

I've reused my soil in 25 gallon fabric pots up to 9x.
I use a nice Clackamas Coots soil mix though which has lots of pumice, biochar and rice hulls for aeration.
The aeration in Fox Farms soils will break down making the soil too heavy and muddy. At minimum should add about 20% pumice by volume to it for better long term aeration that won't break down or float to the top.
I leave the rootballs in the pots, I reamend the soil with Craftblend.
Mine is a Living Organic Soil so I have worms and rove beetles and predator mites and usually springtails in my soil so fungus gnats or other soil borne pest have no chance to propagate.

I scratch the craftblend into the top 2" of soil, then add a big handful of Bokashi all over the top which will help break down the old roots , the worms help break down the roots plus eat the amendments and distribute it through the soil in fresh worm castings.
I plant a cover crop of several types of clover, Flax, buckwheat and peas and let the soil sit for a month and rejuvenate, then cut down the cover crop and put it under the thick mulch layer for the worms.
Up to a point my soil gets better with age, the main limitation is pot size.
In a small 10 gallon pot you'll need to change your soil after a couple grows.
25 gallon pots if you amend properly, have worms and a thick layer of mulch and let it sit a month in between you can get probably 10 grows or more.
If I had a 4x8 bed of LOS then I could reuse indefinitely with proper re-amend and probably do a soil test every 4 to 5 years.

 

[732002]

I see reamending as a continuous process, I mix in fertilizer between grows and top dress during.
As the plants take nutrients out I'm constantly replacing.
I don't have space for pots over 3G indoors, outdoors autos in 10 gallon fabric so roots are free to grow
down into decent garden soil if they feel the need.

 

[Wildbilly]

I reuse my soil 5 or 6 times and keep adding in new soil as needed, as it gets lost in the process. I use almost exclusively Fox Farm Ocean Forest. The only place that I use Happy Frog is when starting new plants in solo cups. Happy Frog is mostly sphagnum moss, and after 2 or 3 runs, it will start to break down, and when it does the soil will go acidic and it will be hard to grow cannabis in it. Your 50/50 mix is going to have this problem on your third grow with that soil. As you move into the future, stop mixing 50/50, and use Happy Frog only for what it was designed for, for starting new plants. Ocean Forest is a rich organic soil and it will draw bugs to it between grows. Be sure to use a good systemic insecticide on that soil before the new grow gets going too long, or you are very likely to have fungus gnats and even aphids.

Thanks for the info on Happy Frog. I'll use it for new plants only. Can you recommend a good systemic insecticide?

 

[Emilya Green]

Thanks for the info on Happy Frog. I'll use it for new plants only. Can you recommend a good systemic insecticide?

@Sierra Natural Science SNS-209, good stuff, and as a sponsor they give a discount to members here that will offset most of the shipping charges.