Kingrow1
Well-Known Member
Soil Grow Guide.
Soil
So you have decided to grow some 'marijuana'. Good choice my friend but what soil are you going to use and how do you know wether it will do the job or leave you with a dead plant? There is no easy way to explain the intricate nature of soil, it is a complex mix of many additives, minerals, semi composted and composted material, microbes, bacteria and normally peat. Most soil companies like to give you a few weeks of nutrients to allow for strong growth but after this you are on your own. There is also a big difference between seedling soil and flowering soil. Allow me to pick up on a few of these points for you-
Seedling soil This is a fine grade soil which allows roots to penetrate it easily. It should be light and airy as well as being weak in nutes so as not to burn those tender newly formed roots. Seedling soil is normally labled 'Seedling soil' or 'Light mix', this symbolises that it is suitable for seedlings and has a low/light amount of nutrients present. Only start your seedlings in this type of soil, a small pot is essential as it will only need to be in the soil for the first two weeks or so and then need to be potted up to a slightly stronger soil/compost.
Potting/all-mix/flowering soil/pro-mix This is slightly heavier in nutrients so is suitable for on growing of plants from the seedling stage. It supports healthy strong growth but as with the seedling soil it normally only has enough nutrients for the first few weeks. It is not as fine grade as seedling soil and generally consists of more peat and larger peices of composted material. Both seedling and flowering soil may come premixed with perlite or vermiculite saving you the job.
Topsoil This is just the soil on its own, a mixture of organic matter and things like clay, minerals etc. Although it is rich in organic matter it is also too heavy for indoor plant pots and has not been amended with peat or other drainage properties. Steer clear of this as its not good on its own for growing plants and outdoors is added to the top of soils or mixed in with existing soils to amend them. Leave this soil alone if you are inexperienced with it and stick to the already prepared soils available.
Perlite Perlite is a volcanic mineral that is expanded under pressure. It is sterile with a neutral pH and contains many tiny, closed cells or bubbles. The surface of each particle is covered with tiny cavities which provide an extremely large surface area. These surfaces hold moisture and nutrients and make them available to plant roots. In addition, because of the physical shape of each particle, air passages are formed which provide optimum aeration and drainage. Add anywhere between ten and fifty percent to your soil dependidng on needs but to start off with add only ten to twenty percent as any more will cause you to struggle.
Vermiculite This is pretty much the same as perlite but with a better water and nutrient holding capability. It also contains small amounts of magnesium and iron so is an added benifit to any soil.
Both perlite and vermiculite dust is dangerous to breath in and acts as a lung irritant in similar ways to asbestos so either wet it before use to stop dust particles becoming airborn or wear a mask.
Hydroton Expanded clay pebbles, they provide drainage properties when mixed in the soil and again are similar to perlite and vermiculite by being able to store water and nutes but these capabilities are limited. They are bigger in size then perlite and vermiculite so not really suitable to small plant pots.
Now we have a quick run down of the types of soil and what you may mix with them to increase drainage and nutrient holding abilities but there is a lot more to consider. Firstly most soils as we know are for the large part peat based with anywhere from twentyfive to sixty percent total volume. Lets deal with the peat issue as it is the main reason for crop failure when soil growing.
Peat Most indoor garden soils seem to contain peat, peat moss is a type of sphagnum moss, used in potting soil mixes. It provides drainage and acidity to the mix. Peat moss helps retain water, yet allows oxygen to be available to the root systems of the potted plant. Because the peat moss produces acid conditions in soil a buffer is often needed to raise the pH back up. Sphagnum peat moss has a pH of about 3-4. Most peat moss comes from either canada or ireland and is dug out of wetland bogs. The most common pH amendment for peat based soils is dolomite limestone. This is added to the soil to counteract the acidic nature of the peat. So you see most peat based soils will end up too acidic for marijuana growth and hence a major problem.
Why soil companies refuse to add enough lime to pre bagged soil is very strange and quite often leaves the gardener having to add the extra or suffer from acidic growing conditions. marijuana loves the pH of soil to be between 6.4 and 6.8, outside this and nutrient uptake will suffer. Most soil companies pH their soil to between 6.3 and 6.6 so you see that it will not take long for your soil to become acidic and pass below the ideal growing pH. Now dolomite limestone will raise that pH back up to near pH7 and buffer it here so that it counteracts the acid peat with its alkaline properties. About a teaspoon per litre or tablespoon per gallon is a good starting point with any extra needed being topdressed in the soil and watered in. Other forms of lime that are plant friendly are calcium carbonate (dosen't contain magnesium), aglime, sea shells, etc etc, just make sure you never use hydrated lime, quicklime, hydraulic lime or any other building product that contains lime. The lime in these products releases so quickly that it burns plant roots and causes heat reactions with the water. Please stick to garden and plant freindly lime or you will again have killed your plant.
Dolomite/garden limeThis is a sedimentary rock made up of calcium and magnesium carbonate. It can be of a coarse or fine grade and even a powder. The finer the grade the faster it will act so we are only concerned with the fine grade or the powder. The powder giving almost instant results and the fine grade taking a few weeks to start to buffer the soil back up to near pH7. The ratio of calcium to magnesium is about 3:1. Most soils already contain some lime in some form but all seem to be lacking the right amount.
So we are starting to see the basics of soil and how we would go about making a viable soil mix which will grow most strains of marijuana. Mix these ingredients thoroughly as if mixing a cake. You see how we start of in seedling soil in small pots and when the soil is full of roots and plant has established itself we re-pot up to a stronger soil in a bigger pot ensuring that the plant has a constant and increasing supply of nutrients. We add perlite or vermiculite or hydroton to increase the drainage of the soil and stop it being waterlogged and lime to counter act the pH of peat and fertilizers.
Now let us pause here and try to answer a few questions that you may have as if i haven't explained this already!! Soil is a medium in which the plants grow, they do not EAT the soil but absorb nutrients suspended in water that the soil holds. As well as absorbing these nutrients the plant needs to breath and drink. They obviously drink and absorb nutrients at the same time as water needs to be present for nutrient absorbtion but how the hell are those roots gona breath when they are surrounded by wet soil? Let me cover you in wet soil and see if you can breath! No you can't and neither can the plant so we want to let the soil dry and allow air into the root zones. Soil is not solid, it is light and fluffy with lots of air pockets and gaps, this is how air enters the soil. When the soil is wet water occupies these air spaces so no air can penetrate down to the roots. The aim is to get the soil to evenly almost dry out, not so it is bone dry but so that there is only a little moisture left. You might notice the plant pot getting lighter as the soil dries and this is the best way to judge when the soil is needing water or not, obviously it will be very light when it needs water! Perlite, vermiculite and hydroton promote drainage and allow the soil to dry quicker. You want the soil to dry roughly every five days so if it dries in three you have to much perlite etc but if it takes eight days to dry you need to amend the soil by adding more perlite etc. I don't expect you to get the amount of perlite to soil ratio right overnight, add what i recomend and go from there.
Now we have made our soil mix and added some lime if needed or the soil has peat products in it, we have good drainage and the soil dries every few days and gives us regular wet and dry cycles. Other factors will affect us as well like the temperature and humidity of the grow room but these are other topics. We are set to go.
Is there anymore to this i hear you wonder, yes there is and a lot of it so lets carry on with a few more subtopics to do with buying soil. When i mentioned that most soil companies add enough nutrients to feed the plant for the first few weeks i omitted to say that there are some companies who add enough ferts to last up to four months. Miracle gro is the most popular but they are diversifying a little with all the complaints they get over their soils. What they add to supply the plants with enough nutrients for this extended period of time are time released fertilizers.
Time release fertilizers A time released fertilizer is a solid form fertilizer, usually in powder or small granules that are either sprinkled on top of the soil (top dressed) or mixed into the soil before planting. The outer layer is insoluble but permeable so nutrients are released slowly in a controlled way over a set period. These can be organic or inorganic, organic time release fertilizers consist of blood, bone meal and fish. Inorganic time release fertilizers such as the ones in miracle gro consist of chemicals. They are hard to control and not really suitable because they lack accuracy and cannot be flushed from the soil easily.
Did i just say don't buy miracle gro! No but being new to gardening i suggest you avoid this product as you will not be able to regulate the level of fertilizers. Leave this product to the pros, miracle gro gets a bad rep but i would have no problem growing in it. It is a different type of soil mix which without experience will lead to failure or problems. Keep it simple at all times and avoid that miracle gro.
John Innes/west + This is basically the base fertilizer used in soils, there are others but these seem to be the most popular. They are in there simplests forms mixes of base ingredients such as hoof and horns, superphosphates and other mineral and nutrient rich ingredients. It is these formulas which provide the few weeks of nutrients on which your plant lives on before you start to apply fertilizers. You will often see soil advertised with added 'John Innes' or 'West+' etc etc. This is what they mixed with the peat, loam, sand etc to make your potting soil or compost.
So where do we go from here? Maybe a basic knowledge of the masses of life that will be populating the soil during your growing time. Unless the soil is sterile or dead you will be providing a home to a lot of other things other than marijuana.
Microherd All soil/compost microbes are important for proper soil health and compost decomposition. In addition to the soil microbes, you got earthworms, sowbugs, soldier fly larvae, etc. However, even inside the internal organs and cells of these larger beneficial soil organisms, you still got the amazing soil/compost microbes working constantly digesting pounds and pounds of insoluble organic material into soluble nutrients and constantly improving the soil's health and texture. When we use the term microbes or microherd, we mean not only just bacteria, but also fungi and other species. Now salt based chemical fertilizers wipe these guys out whereas organic fertilizers promote their growth. These little organisms brak down organic matter into food for the plant whereas chemical fertilizers feed the plant directly. Ever wondered where all the leaves go after autumn? the microherd break them down into leaf humus and a nutrient rich soil.
The overall choice is yours so wether you choose the organic route and feed the microherd which in turn feed your plant or the chemical fertilizers which cut out and kill the middle man (the microherd) and feed the plant directly with soluble nutrients you still are feeding the plant with soil as the planting medium. I prefer the organic route as it is slightly more forgiving with fertilizer overdoses and pH but feel that the chemical fertilizers provide quicker and more measured doses of nutrients. You must keep the soil healthy for the microherd to work to their optimun ability.
The microherd lead me onto my next topic, compost. Maybe i should have dealt with it earlier but i wanted to let you understand the concept of the microherd first as this is the fundamental basis of compost. Some companies label their soil as compost which can be confusing where as some call their soil soil. First let me explain compost.
CompostThis is organic matter that has been broken down into plant available nutrients by the microherd. It is nutrient rich and at the base of good plant growth. Compost on its own is often too strong to grow plants in as the over abundance of nutrients easily burns plant roots making growth near impossible. As well as organic food and forestry sources compost can also be made from farm products. Manure is partially decomposed organic matter just like compost. Bacteria and organisms break the animal feed down during digestion which make it rich in plant available nutrients. Leaf humus is another type of compost popular with plants.
So we see that compost is essential but too strong to use for most plants on its own, it needs futher mixing with somthing like peat to weaken it down, for this reason i believe soil companies use the word compost when describing their soil mix. I all too often buy soil that is labeled as just flowering compost or all purpose compost but it is barely thirty percent compost. Do not get confused by this, soil companies like the word compost and label their soil as compost but it rarely is just compost and sometimes not even the main ingredient in the soil mix. This is not somthing you need to buy or mix in to your soil, your soil should already contain a certain amount pre-mixed when you buy it.
So soil companies do most of the work leaving you to judge the additional drainage properties and pH adjustments. Pay attention to these areas and you will have the perfect medium with which to grow in. There is a lot of different soils and composts out there and each will have its own soil mix, you need to work out what it is and amend it to what you want. Some seem to flourish with straight soil out of the bag but additions such as peat and perlite cause a lot of problems to new growers. Rarely is the soil good enough to support three months of plant growth without you first amending it.
I hope this will be of use to the novice and new grower, it really is simple if you know what you are doing but countless grow have failed because of acid conditions and no lime or too poor drainage. Learn to mix your own soil to get what you want out of it. These are the basics and only you can take it to the next level. I never got good results indoors in plant pots without good soil, the right amount of perlite and lime. Essentials such as a digital pH meter make it a whole lot easier and accurate too, i cannot stress the importance of buying one of these and see it as a must for new growers, the money you pay for one of these will be nothing compared to the extra yeild you achieve.
As always good luck, keep it simple and grow that weed!
So you have decided to grow some 'marijuana'. Good choice my friend but what soil are you going to use and how do you know wether it will do the job or leave you with a dead plant? There is no easy way to explain the intricate nature of soil, it is a complex mix of many additives, minerals, semi composted and composted material, microbes, bacteria and normally peat. Most soil companies like to give you a few weeks of nutrients to allow for strong growth but after this you are on your own. There is also a big difference between seedling soil and flowering soil. Allow me to pick up on a few of these points for you-
Seedling soil This is a fine grade soil which allows roots to penetrate it easily. It should be light and airy as well as being weak in nutes so as not to burn those tender newly formed roots. Seedling soil is normally labled 'Seedling soil' or 'Light mix', this symbolises that it is suitable for seedlings and has a low/light amount of nutrients present. Only start your seedlings in this type of soil, a small pot is essential as it will only need to be in the soil for the first two weeks or so and then need to be potted up to a slightly stronger soil/compost.
Potting/all-mix/flowering soil/pro-mix This is slightly heavier in nutrients so is suitable for on growing of plants from the seedling stage. It supports healthy strong growth but as with the seedling soil it normally only has enough nutrients for the first few weeks. It is not as fine grade as seedling soil and generally consists of more peat and larger peices of composted material. Both seedling and flowering soil may come premixed with perlite or vermiculite saving you the job.
Topsoil This is just the soil on its own, a mixture of organic matter and things like clay, minerals etc. Although it is rich in organic matter it is also too heavy for indoor plant pots and has not been amended with peat or other drainage properties. Steer clear of this as its not good on its own for growing plants and outdoors is added to the top of soils or mixed in with existing soils to amend them. Leave this soil alone if you are inexperienced with it and stick to the already prepared soils available.
Perlite Perlite is a volcanic mineral that is expanded under pressure. It is sterile with a neutral pH and contains many tiny, closed cells or bubbles. The surface of each particle is covered with tiny cavities which provide an extremely large surface area. These surfaces hold moisture and nutrients and make them available to plant roots. In addition, because of the physical shape of each particle, air passages are formed which provide optimum aeration and drainage. Add anywhere between ten and fifty percent to your soil dependidng on needs but to start off with add only ten to twenty percent as any more will cause you to struggle.
Vermiculite This is pretty much the same as perlite but with a better water and nutrient holding capability. It also contains small amounts of magnesium and iron so is an added benifit to any soil.
Both perlite and vermiculite dust is dangerous to breath in and acts as a lung irritant in similar ways to asbestos so either wet it before use to stop dust particles becoming airborn or wear a mask.
Hydroton Expanded clay pebbles, they provide drainage properties when mixed in the soil and again are similar to perlite and vermiculite by being able to store water and nutes but these capabilities are limited. They are bigger in size then perlite and vermiculite so not really suitable to small plant pots.
Now we have a quick run down of the types of soil and what you may mix with them to increase drainage and nutrient holding abilities but there is a lot more to consider. Firstly most soils as we know are for the large part peat based with anywhere from twentyfive to sixty percent total volume. Lets deal with the peat issue as it is the main reason for crop failure when soil growing.
Peat Most indoor garden soils seem to contain peat, peat moss is a type of sphagnum moss, used in potting soil mixes. It provides drainage and acidity to the mix. Peat moss helps retain water, yet allows oxygen to be available to the root systems of the potted plant. Because the peat moss produces acid conditions in soil a buffer is often needed to raise the pH back up. Sphagnum peat moss has a pH of about 3-4. Most peat moss comes from either canada or ireland and is dug out of wetland bogs. The most common pH amendment for peat based soils is dolomite limestone. This is added to the soil to counteract the acidic nature of the peat. So you see most peat based soils will end up too acidic for marijuana growth and hence a major problem.Why soil companies refuse to add enough lime to pre bagged soil is very strange and quite often leaves the gardener having to add the extra or suffer from acidic growing conditions. marijuana loves the pH of soil to be between 6.4 and 6.8, outside this and nutrient uptake will suffer. Most soil companies pH their soil to between 6.3 and 6.6 so you see that it will not take long for your soil to become acidic and pass below the ideal growing pH. Now dolomite limestone will raise that pH back up to near pH7 and buffer it here so that it counteracts the acid peat with its alkaline properties. About a teaspoon per litre or tablespoon per gallon is a good starting point with any extra needed being topdressed in the soil and watered in. Other forms of lime that are plant friendly are calcium carbonate (dosen't contain magnesium), aglime, sea shells, etc etc, just make sure you never use hydrated lime, quicklime, hydraulic lime or any other building product that contains lime. The lime in these products releases so quickly that it burns plant roots and causes heat reactions with the water. Please stick to garden and plant freindly lime or you will again have killed your plant.
Dolomite/garden limeThis is a sedimentary rock made up of calcium and magnesium carbonate. It can be of a coarse or fine grade and even a powder. The finer the grade the faster it will act so we are only concerned with the fine grade or the powder. The powder giving almost instant results and the fine grade taking a few weeks to start to buffer the soil back up to near pH7. The ratio of calcium to magnesium is about 3:1. Most soils already contain some lime in some form but all seem to be lacking the right amount.So we are starting to see the basics of soil and how we would go about making a viable soil mix which will grow most strains of marijuana. Mix these ingredients thoroughly as if mixing a cake. You see how we start of in seedling soil in small pots and when the soil is full of roots and plant has established itself we re-pot up to a stronger soil in a bigger pot ensuring that the plant has a constant and increasing supply of nutrients. We add perlite or vermiculite or hydroton to increase the drainage of the soil and stop it being waterlogged and lime to counter act the pH of peat and fertilizers.
Now let us pause here and try to answer a few questions that you may have as if i haven't explained this already!! Soil is a medium in which the plants grow, they do not EAT the soil but absorb nutrients suspended in water that the soil holds. As well as absorbing these nutrients the plant needs to breath and drink. They obviously drink and absorb nutrients at the same time as water needs to be present for nutrient absorbtion but how the hell are those roots gona breath when they are surrounded by wet soil? Let me cover you in wet soil and see if you can breath! No you can't and neither can the plant so we want to let the soil dry and allow air into the root zones. Soil is not solid, it is light and fluffy with lots of air pockets and gaps, this is how air enters the soil. When the soil is wet water occupies these air spaces so no air can penetrate down to the roots. The aim is to get the soil to evenly almost dry out, not so it is bone dry but so that there is only a little moisture left. You might notice the plant pot getting lighter as the soil dries and this is the best way to judge when the soil is needing water or not, obviously it will be very light when it needs water! Perlite, vermiculite and hydroton promote drainage and allow the soil to dry quicker. You want the soil to dry roughly every five days so if it dries in three you have to much perlite etc but if it takes eight days to dry you need to amend the soil by adding more perlite etc. I don't expect you to get the amount of perlite to soil ratio right overnight, add what i recomend and go from there.
Now we have made our soil mix and added some lime if needed or the soil has peat products in it, we have good drainage and the soil dries every few days and gives us regular wet and dry cycles. Other factors will affect us as well like the temperature and humidity of the grow room but these are other topics. We are set to go.
Is there anymore to this i hear you wonder, yes there is and a lot of it so lets carry on with a few more subtopics to do with buying soil. When i mentioned that most soil companies add enough nutrients to feed the plant for the first few weeks i omitted to say that there are some companies who add enough ferts to last up to four months. Miracle gro is the most popular but they are diversifying a little with all the complaints they get over their soils. What they add to supply the plants with enough nutrients for this extended period of time are time released fertilizers.
Time release fertilizers A time released fertilizer is a solid form fertilizer, usually in powder or small granules that are either sprinkled on top of the soil (top dressed) or mixed into the soil before planting. The outer layer is insoluble but permeable so nutrients are released slowly in a controlled way over a set period. These can be organic or inorganic, organic time release fertilizers consist of blood, bone meal and fish. Inorganic time release fertilizers such as the ones in miracle gro consist of chemicals. They are hard to control and not really suitable because they lack accuracy and cannot be flushed from the soil easily. Did i just say don't buy miracle gro! No but being new to gardening i suggest you avoid this product as you will not be able to regulate the level of fertilizers. Leave this product to the pros, miracle gro gets a bad rep but i would have no problem growing in it. It is a different type of soil mix which without experience will lead to failure or problems. Keep it simple at all times and avoid that miracle gro.
John Innes/west + This is basically the base fertilizer used in soils, there are others but these seem to be the most popular. They are in there simplests forms mixes of base ingredients such as hoof and horns, superphosphates and other mineral and nutrient rich ingredients. It is these formulas which provide the few weeks of nutrients on which your plant lives on before you start to apply fertilizers. You will often see soil advertised with added 'John Innes' or 'West+' etc etc. This is what they mixed with the peat, loam, sand etc to make your potting soil or compost.
So where do we go from here? Maybe a basic knowledge of the masses of life that will be populating the soil during your growing time. Unless the soil is sterile or dead you will be providing a home to a lot of other things other than marijuana.
Microherd All soil/compost microbes are important for proper soil health and compost decomposition. In addition to the soil microbes, you got earthworms, sowbugs, soldier fly larvae, etc. However, even inside the internal organs and cells of these larger beneficial soil organisms, you still got the amazing soil/compost microbes working constantly digesting pounds and pounds of insoluble organic material into soluble nutrients and constantly improving the soil's health and texture. When we use the term microbes or microherd, we mean not only just bacteria, but also fungi and other species. Now salt based chemical fertilizers wipe these guys out whereas organic fertilizers promote their growth. These little organisms brak down organic matter into food for the plant whereas chemical fertilizers feed the plant directly. Ever wondered where all the leaves go after autumn? the microherd break them down into leaf humus and a nutrient rich soil.The overall choice is yours so wether you choose the organic route and feed the microherd which in turn feed your plant or the chemical fertilizers which cut out and kill the middle man (the microherd) and feed the plant directly with soluble nutrients you still are feeding the plant with soil as the planting medium. I prefer the organic route as it is slightly more forgiving with fertilizer overdoses and pH but feel that the chemical fertilizers provide quicker and more measured doses of nutrients. You must keep the soil healthy for the microherd to work to their optimun ability.
The microherd lead me onto my next topic, compost. Maybe i should have dealt with it earlier but i wanted to let you understand the concept of the microherd first as this is the fundamental basis of compost. Some companies label their soil as compost which can be confusing where as some call their soil soil. First let me explain compost.
CompostThis is organic matter that has been broken down into plant available nutrients by the microherd. It is nutrient rich and at the base of good plant growth. Compost on its own is often too strong to grow plants in as the over abundance of nutrients easily burns plant roots making growth near impossible. As well as organic food and forestry sources compost can also be made from farm products. Manure is partially decomposed organic matter just like compost. Bacteria and organisms break the animal feed down during digestion which make it rich in plant available nutrients. Leaf humus is another type of compost popular with plants.So we see that compost is essential but too strong to use for most plants on its own, it needs futher mixing with somthing like peat to weaken it down, for this reason i believe soil companies use the word compost when describing their soil mix. I all too often buy soil that is labeled as just flowering compost or all purpose compost but it is barely thirty percent compost. Do not get confused by this, soil companies like the word compost and label their soil as compost but it rarely is just compost and sometimes not even the main ingredient in the soil mix. This is not somthing you need to buy or mix in to your soil, your soil should already contain a certain amount pre-mixed when you buy it.
So soil companies do most of the work leaving you to judge the additional drainage properties and pH adjustments. Pay attention to these areas and you will have the perfect medium with which to grow in. There is a lot of different soils and composts out there and each will have its own soil mix, you need to work out what it is and amend it to what you want. Some seem to flourish with straight soil out of the bag but additions such as peat and perlite cause a lot of problems to new growers. Rarely is the soil good enough to support three months of plant growth without you first amending it.
I hope this will be of use to the novice and new grower, it really is simple if you know what you are doing but countless grow have failed because of acid conditions and no lime or too poor drainage. Learn to mix your own soil to get what you want out of it. These are the basics and only you can take it to the next level. I never got good results indoors in plant pots without good soil, the right amount of perlite and lime. Essentials such as a digital pH meter make it a whole lot easier and accurate too, i cannot stress the importance of buying one of these and see it as a must for new growers, the money you pay for one of these will be nothing compared to the extra yeild you achieve.
As always good luck, keep it simple and grow that weed!
