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Optimal Soil for Growing Cannabis

When choosing soil for growing cannabis, think about three important things: how well water can it drain, the soil’s pH (how acidic or basic it is), and what it’s made of.

Soil for Growing Cannabis

Choosing the right soil is crucial for cannabis growth. It must offer optimal drainage, crumbly texture, and a slightly acidic pH (6-6.8). Texture matters—avoid clumps or stones.

Sandy soils wash away; clayey ones hold too much water. Maintain pH with manure and compost. Organic additions like worm castings release vital elements gradually, supporting microbial life in the soil.

Combine 2 parts potting soil, 1 part organic compost (worm castings or sheep manure), and 1 part perlite for a well-balanced mix, maintaining the right moisture level for robust cannabis growth.

BiG Plant Science fertilizer, with chelated salts, ensures fast nutrient availability.

Soil Texture and Drainage

Good soil has the right texture. It should let the roots of your cannabis plant grow freely and let water drain through easily. If the soil has big clumps, stones, or is too packed, it’s not good for your plant’s roots. The best soil for cannabis feels “crumbly” when you squeeze it – not too wet or too dry. Sandy soils wash away, and clayey soils hold too much water. Bad drainage can drown the roots, so the soil should let the plant get a bit dry before watering.

Soil pH

Cannabis plants like the soil to be a bit acidic, with a pH between 6 and 6.8. Keeping the pH right is easier in soil than in other growing mediums. Stuff like manure and compost in the soil helps keep the pH in the right range. When you feed your plants, make sure the solution you add is also in that pH range. Most store-bought soils are in the right pH range, so it’s easier to start with them. Check the pH yourself to avoid problems. If the pH is off, your plant might not get the nutrients it needs, and that’s not good!

Adding organic materials like worm castings, manure and compost can really help your plants grow. These additions contain elements like phosphorus, potassium, and nitrogen and are slowly released over time and also adding your soil a microbial life.

Compost and Other Amendments

Enhancing your plant’s success relies heavily on the nutrients present in the soil. Incorporating natural elements like worm castings, manure, and compost can significantly boost plant growth. These additives contain essential elements such as phosphorus, potassium, and nitrogen, gradually released as needed by your plants.

A fertilizer like BiG Plant Science is made with chelated salts. Don’t be confused by the word salt though, chelated salts allow base elements to become water soluble and it’s the fastest way to feed your plants.

These nutrients are immediately available for root system and can be flushed out in the case of over fertilization. BiG Plant Science will help the plant grow quickly while the composts in the soil help make up the difference between feedings and avoid nutrient buildup.

Basic Soil Mix for Cannabis

  • 2 Parts Potting Soil
  • 1 Part Organic Compost (Vermicompost (Worm Castings) or Sheep Manure are good choices)
  • 1 Part Perlite
    Mix up the potting soil, organic compost, and perlite really well. You also need to add a little bit of water. The soil should be moist enough that it feels spongey when you squeeze your hand around it but not dripping wet.

Soil for Growing Cannabis

Find out how much nutrients you need for your grow

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