Soil Selection for the Indoor Grower:
Some growers have asked me if it would be better to use soil from their outside garden in order to start their seeds indoors. I have advised against this practice for several reasons. Number one, it is more difficult to control the variables that lead to proper germination. The chemistry of outside soil varies drastically from region to region and even from yard to yard and this fact makes utilizing outside soil a more risky proposition for starting seeds indoors. It is much easier to control variables linked to soil chemistry with a type of potting soil. Another reason utilizing outdoor soil could be troublesome is due to the potential for weed seeds to germinate and for outdoor disease spores to infiltrate. Once again, utilizing a potting soil mix reduces potential problems and ultimately provides a more reliable and stable medium in which to germinate seeds.
The potting soil that I selected is mixed with beneficial microbes and fungi which helps to break down organic matter and feed the plant roots. I have recently been utilizing Happy Frog which contains a healthy batch of earthworm castings, bat guano, as well as fine-screened pH balanced forest humus. The plants feed and thrive on the organic material during the grow process and the blend helps to support root development during the primary and secondary stages of development. I have had success utilizing this type of potting soil and I even place some in the outside garden to support the transition of the plants that I select to place in the garden.
The Soil Mixture I Used To Start My Seeds Indoors:
In addition to the soil, I mixed in a general hydroponic organic growing medium. The medium was CocoTek premium grade natural coconut coir. Some of the positive aspects of utilizing CocoTek in your soil mixture to start seeds are as follows:
- pH neutral
- excellent water holding capacity
- helps to increase nutrient retention
- provides essential aeration
- it is environmentally friendly -it is natural
- it is also helps to support the transition to an outdoor placement if that is the goal
The ratio of soil to CocoTek medium I used was 1:1. The coir I purchased came in brick from and needed to be broken apart and then hydrated. The CocoTek coir brick is densely packed and so I used a screw driver and a hammer to break the brick apart. I only used half of the brick and poured in approximately 3/4 gallon of water to hydrate the coir. I did all of this in a standard 5 gallon bucket. The coir hydrated quickly and expanded. I was very impressed with the water holding ability of the coir. It should be noted that coir holds around 8 times its dry weight in water. Once the coir was fully hydrated, I measured the amount of coir in the bucket and then included the same amount of soil. After the soil was added and mixed thoroughly, I was ready to scoop it out and transfer it into my various seed starting units.
Coir Organic Growing Medium versus Peat Moss Growing Medium:
It should be noted that some growers choose to use peat moss as a medium to mix in with their soil. More growers are turning away from peat moss for various reasons and although an in-depth review of the reasons is beyond the scope of this specific post, I will briefly run through the basic disadvantage of using peat moss over coir.
One reason I prefer to use the CocoTek growing medium over a peat moss medium is because the CocoTek is an organic Coir. Coir is the fiber from the organic husk of a coconut and is a byproduct of coconut processing. Most coconut fiber comes from places like India or Sri Lanka. Peat moss comes from the peat bogs filled with decomposed sphagnum moss mostly found in the U.S. and Canada. Sustainability is one key factor that supports my decision to use the coconut fiber. Peat moss is considered, by many ecologists, to be harvested at a non-sustainable rate. Basically, it is on the ecologists’ endangered list. Peat bogs, once harvested, can take up to a quarter century to renew. The coconut fiber is a waste product of the coconut harvest. Since coconut fiber is readily available and continuously grows on trees, it is a more sustainable resource than peat moss.
One other disadvantage of using peat moss that I’d like to mention is the acidity levels. Peat moss is much more acidic than a coir fiber medium. The approximate pH level of peat moss is going to be around 3.5 – 3.9. This might be good for plants that like soil rich in acid, but many plants do not. Coir fiber has a pH range from 5.5 to 6.5 which supports a larger range of plants. Coir is better suited for a wider range of plants and for this reason, coir organic growing medium is a better choice.
Using coconut fiber as a medium to mix with your soil is not only beneficial for the reasons listed above, but it is also more environmentally friendly to use.
Putting to Soil/Coir Mix into the Cells:
Be sure to mix the soil/coir mixture well prior to transferring into potting cells. During the transfer, do not pack the mixture densely into the cells but allow mixture to settle into the cell by tapping the cell walls. Fill approximately 3/4 of the volume inside the cell with the soil/coir mixture.
Starting the seeds using the soil and coir mixture:
One benefit I noticed when using coir over peat moss was the ability to absorb and maintain water retention . It wet more easily and required less time to become saturated than peat moss. This aspect made the watering process easier for me. My soil mixture maintained an appropriate moisture level throughout the seed-starting process. The entire cell that contained the starting seeds maintained a better moisture level throughout the process which made watering more efficient and moisture deficiencies non-existent. The soil did not dry out at any point and water was not wasted due to poor water retention. I checked on my cells twice a day to maintain the appropriate moisture levels in the soil. It was relatively quick and painless each time I checked. The soil/coir mixture stayed moist and retained water to ensure excellent root formation and development and to minimize the chance of over saturation. Using this mixture was a positive experience and one that I will repeat in future growing.
Putting the Seed into the Soil:
Prior to placing the seeds into the soil cells that were filled with the soil-coir mix, I first added some water. Specifically, I added 10ml of water to each cell to dampen the soil/coir mixture in order to prepare the soil for seed insertion. I have found that when placing the seeds into the cells, I have more efficient outcomes when adding the water first. The depth at which the seeds were placed into the soil was dependent on the care and maintenance guidelines linked to each specific plant seed type. On average, the seed depth was set at 1/4 of an inch. I used three or more seeds in every cell since it is possible that not all seeds will germinate in each cell. Thinning of plants in each cell can be performed later if necessary.
Temperature Control for Germinating Seeds:
I kept the ambient room temperature around 70 degrees during the germination process. This temperature was enhanced slightly directly under my grow light during lighting hours. Although the light is not necessary to start the seeds, I like to use the light to support a consistent approach and a repetitive structured pattern to each day. Growers can also choose to utilize a plastic bag or a plastic sheet covering over their seeds to enhance the germinating temperatures or the moisture maintenance factors (greenhouse effect), but I did not do this during my germinating process. Using plastic can be troublesome if appropriate airflow is not maintained under the plastic. Lack of airflow under plastic can lead to mold spore proliferation. Approximately half of my cells sprouted in six days. The rest of the cells, I had a total of 21 to start this round, sprouted within the first 12 days. Since I had a variety of seed types, varied sprouting times were expected.
Once the seedlings begin to grow and true leaves appear, active photosynthesis is necessary in order for the plant to continue growing in a healthy manner. Approximately 12 to 16 hours of light will be necessary in order for active photosynthesis and healthy growth. If more than one seedling is growing in each cell, thin the less desirable sprouts out by cutting them or, if the sprouts are far enough apart, transfer them into a separate pot. Do not trying pulling the sprout out or separating if they are close as this action may damage the root system of the more desirable plant that you wish to keep. If the cell that you started the seedling in is smaller than 3 inches in depth, you may want to consider transferring the sprout to a pot that is three to four inches and will allow for adequate space for root development. Once the roots have room to spread out and develop and adequate lighting is provided, it is time to grow big!