Rumman69
Luckily for you I have 16 years experience with organic farming and am a science nerd with some free time tonight.
The texture of the medium determines its water-holding and draining properties. Marijuana must have a well-drained medium for healthy growth. Soils that hold too much water or hold it unevenly can drown the roots, leading to poor growth or death of the plant. In a well- drained soil the roots are in contact with air as well as water. Soils that have too much clay, or are overly rich in compost or other organic matter, tend to hold too much water and not enough air.
This condition worsens in time. This is especially true of the soil in pots.
You can determine the texture of your soil from its appearance and feel. Dry soil should never cake or form crusts. Dry or slightly moist soil that feels light-weight, airy, or spongy when squeezed, and has a lot of fibrous material, will hold a lot of water. Mix it with materials which decrease its water-holding capacity, such as sand, perlite.
Wet soil should remain spongy or loose and never sticky. A wetted ball of soil should crumble or separate easily when poked.
Soil that feels heavy and looks dense with fine particulate matter, or is sandy or gritty, will benefit by being loosened and lightened with fibrous materials such as vermiculite, or sometimes sphagnum moss.
Soil Conditioners to Improve Texture
Perlite (expanded sand or volcanic glass) is a practically weightless horticultural substitute for sand. Sand and perlite contribute no nutrients of their own and are near neutral in pH. They hold water, air, and nutrients from the medium on their irregular surfaces and are particularly good at aerating the soil.
Vermiculite (a micaceous material) and sphagnum moss contribute small amounts of their own nutrients and are near neutral in pH. They hold water, air, and nutrients in their fiber and improve the texture of sandy or fast-draining soils. Similar mixes are made of ground vermiculite and sphagnum moss, and are fortified with a small amount of all the necessary nutrients. They are available at neutral pH, are good soil conditioners, and are also useful for germinating seeds.
In the case of your soil..
Sphagnum and Peat Moss (certain fibrous plant matter) are sometimes used by growers to improve water holding and texture. Both work well in small amounts (10 to 15 percent of soil mixture). In excess, they tend to make the medium too acidic after a few months of watering.
So with a soil like yours they are sometimes manufactured entirely from wood and bark fiber, composts, and soil conditioners. These mixes are made to hold a lot of water and slowly release nutrients over a period of time, which is what most house plants require. For marijuana, these mixes seldom contain enough nutrients to support healthy growth for more than a couple of months. (Their N is usually low, P adequate, and K usually very high.) They work best when sand or perlite is added to improve drainage, and fertilizers are added to offset their low nutrient content.
But from my experience in organic botany the npk level is just fine for starters. Sorry to drag on
Long story short
Each soil has its own unique properties. These properties determine how the soil and plants will interact. For our purposes, all soils can be classified as sands, silts, clays, mucks, and loams. And good organic soils are usually a combination of these. If you look carefully at a handful of soil, you may notice sand granules, pieces of organic matter, bits of clay. Etc etc etc. So im sure you'll be just fine. Just make sure they bleed when watering and you'll be good. Your npk levels are just fine for the initial veg process. Facts and opinions may vary. I can't wait to see your plants progess
Any questions???