This brings up an obvious question: “What kind of soil should I use for germination?” At many garden centers, you will find soils that are marketed specifically as ”germination soils”.
Nothing really separates these soils from more conventional soils except that they have certain nutrients and don’t contain any composted material.
Look for soils that have an NPK (Nitrogen-Phosphorus-Potassium) ratio of around 5:1:1 or 8:4:4. Really, any soil with more nitrogen than the other two nutrients will be adequate for germinating marijuana seeds.
The containers you place the soil in are also relatively important. It’s common for growers to use buckets that can hold between 2 and 5 gallons because the root system in a marijuana plant can become quite extensive.
Smaller containers will work for the germination and seedling period, but the plants will need to be transplanted later. Thus, it makes sense to plant the marijuana seeds and leave the plants in a single 2- to 5-gallon bucket for the majority of their lives.
This gives the roots adequate room to grow and thrive while also providing a perfect environment for nutrients and a satisfactory reservoir of water. Also, leaving them in buckets makes them easily transportable.
PH balance A few other things to take into account are the pH balance and the actual texture of the soil. You can feasibly use the same soil throughout the life of the plant if you ensure that water can drain properly (soil texture) and the soil maintains a good pH balance (between 6.0 and 7.0).
The texture is particularly important because soils should neither be too dry nor too moist. Moist soils that have an almost muddy consistency reduce the amount of oxygen that can reach the roots. As long as the roots can “breathe” and still maintain adequate water uptake, the soil should be fine.
Soil control
When you have an indoor marijuana garden you have more control over the soil, so you’ll need to keep an eye on it. Marijuana prefers to grow in a nutrientrich soil that has a neutral pH of around 7.0. Sometimes, however, the pH in the soil can shift quite far out of the acceptable ranges of 6.0 to 7.0. In such cases, you may need to take drastic measures to ensure that the soil does not end the life of your plants.
When pH levels fluctuate, it is often caused by chemical contamination. A soil flush can reduce contamination and balance the pH. However, this is generally not a recommended procedure, although it is sometimes necessary. A soil flush should only be used as a last resort when trying to keep your marijuana plant alive. To do it, place your entire plant, pot included, in a sink.
From there, turn on the faucet and let the water run through the soil so that it eliminates any of the contaminants that might have been harming the plant. The danger of this method is a risk of killing the plant by oversaturation. Too much water is as bad as too many nutrients. But, sometimes flushing the soil is the only way to ensure that additives don’t kill your marijuana plants.
For less severe issues, there are other options. If your soil’s pH level drops below the recommended 6.0 and becomes too acidic, then you can simply add some 22 lime to the soil the next time you water it. This should raise the pH back into an acceptable range between 6.0 and 7.0. If the soil is above 7.0 and, therefore, too alkaline, you might consider adding a mixture of cottonseed meal, lemon peels, and ground coffee.
Some fertilizers are also made to be highly acidic and can lower your soil’s alkalinity if applied.
In any event, it’s always a good idea to keep checking the pH balance of your soil; otherwise, you could be in for a disappointing surprise. Here you can see pH problems, on the left the pH level is too high, on the right the pH level is too low
