The Best Soil for Hemp Seedlings
Whether you’re a professional hemp farmer or a hobby grower, starting seeds can be tricky. The seedling stage is one of the most challenging periods for any cultivator and requires a lot of patience, preparation, and practice to master. If you’d like to get your crop off to a good start, using the best soil for hemp seedlings is essential. Starting seeds in the wrong medium can result in stunted growth and sickly plants—a mistake I’ve admittedly made in the past. So, in this article, we’ll teach you everything you need to know about selecting the right starting soil for your hemp plants.
What Is the Best Starting Soil for Hemp Seedlings?
Not all plants thrive in the same type of soil, and not all soil is ideal for hemp plants. Because hemp seedlings have small, immature roots, they are especially sensitive to soil conditions. As a result, farmers must be careful when choosing a starting soil, as it can make or break their harvest.
A good starting soil should be well-aerated, offer good drainage and moisture retention, and have a slightly acidic pH value. It should also be low in organic matter, as seedlings do not require as many nutrients as mature plants.
We recommend going with a specialized seed-starting mix to plant your hemp seeds. Regular potting soil tends to be very nutrient-dense and, as a result, it could burn or shock the seedlings. It’s also much coarser and doesn’t drain as well.
A high-quality seed-starting mix will contain just the right amount of fertilizer to sustain a young seedling. These mixes also tend to be lighter and fluffier than standard potting soil, allowing the seedlings’ roots to spread throughout the medium effortlessly.
Components of a Good Seedling Soil Mix
When choosing a soil mix for your hemp seedlings, consider the following:
- Water retention and drainage
- pH value
Hemp seedlings grow best in loose and light soil. The plants’ roots penetrate easily through fluffy soil. Also, it will ensure enough oxygen reaches the roots to sustain healthy growth.
If your soil is too compact, try mixing in some coco coir. Coconut fiber can lighten the soil while also making it less rich in nutrients.
Water Retention and Drainage
Because seedlings have a small root zone, they need plenty of moisture in order to survive. A good starting soil should be able to retain enough water to keep the root zone moist; however, it also needs to provide enough drainage to prevent the roots from rotting.
If your soil is drying out too quickly, add 10 to 15 percent vermiculite to the mix. Vermiculite is a heat-treated mineral that is great at improving water retention without making the soil too compacted.
Conversely, you can improve the drainage of the soil by adding 10 to 15 percent perlite. These small, white rocks are excellent at breaking up compacted soil, allowing water to pass through easily.
The pH scale shows a substance’s level of acidity or basicity. The pH value of your soil is essential, as hemp seedlings can only absorb nutrients within a certain pH range.
According to Oregon State University, hemp grows best in soil with a pH of 6.0 to 7.5. If the pH deviates from this range, the plants may not be able to uptake enough nutrients to support healthy growth.
Most store-bought soil mixes fall within the ideal pH range; however, you can use a soil pH test kit to ensure that your soil pH is suitable. If the pH is too low, you can amend the soil with dolomite or agricultural lime to raise it. On the other hand, if the pH is too high, it can be lowered by mixing in elemental sulfur or aluminum sulfate.
Hemp seedlings need only a small amount of nutrients to thrive. Planting them into a nutrient-dense potting soil can lead to curling leaves, burnt leaf tips, stunted growth, and eventually, death.
A good seedling soil mix will contain only enough nutrients to sustain a seedling without overfertilizing it. If you are uncertain of the NPK value of your soil, you can use a soil test kit to determine how nutrient-dense it is.
If there are too many nutrients in your soil, you can dilute it by adding coco coir to the mix. You can also place the soil into a pot and water it heavily to flush out some of the fertilizers.
If you must feed your seedlings with additional nutrients, do so in moderation and only after the first set of true leaves have fully formed. By this point, the plants should be established enough to handle some additional fertilizer.
What Are the 4 Types of Soil?
Soil can be categorized into four types: sandy, silty, clay, and loamy. Each type of soil is composed of different particles and, as a result, has its own unique characteristics.
Sandy soil offers good drainage because it is coarse. On the downside, it is ineffective at retaining water and nutrients. If you use sandy soil, you’ll have to feed and water the plants frequently. Given its poor ability to retain water and nutrients, this soil type is not recommended for growing hemp seedlings.
Clay soil is composed of very small mineral particles and is lacking in organic matter. It retains water effectively but is very compact and does not drain well. Again, this type of soil is not recommended for starting hemp seedlings.
Silty soil has a medium-coarse texture and is rich in minerals and organic matter. This type of soil is easy to work with and has adequate drainage and moisture retention properties. Silty soil makes for a great starting mix for hemp seedlings.
Loamy soil is a blend of silt, clay, sand, and organic compounds, combining the best qualities of each soil type. Loamy soil is light and fluffy and provides excellent drainage and water retention. This is widely regarded as the best type of soil for hemp seedlings; however, it can often be expensive.
The Best Soil for Hemp Seedlings: Final Thoughts
Hemp seedlings can be grown in a variety of soils, but some are more effective than others. The key to producing high-yielding, CBD-rich hemp plants is to provide an optimal environment for growth. A good starting mix will help ensure that your seedlings grow into hardy hemp plants.
What is your preferred soil mix for growing hemp seedlings? Please let our readers know in the comment section below.