Organic farming: Planting steps (4) Seedling cultivation and facilities
Seed germination and seedling growth require careful management of soil, temperature, humidity, and sunlight. While many vegetables can be directly sown outdoors, they often suffer from inadequate care, including improper watering, excessive or insufficient sunlight, and soil-borne pathogens, leading to low germination rates and poorly developed seedlings. In some cases, seedlings may even succumb to disease.
To enhance the germination rates and improve seedling survival, proper seedling cultivation techniques are essential.
If you wish to enjoy seasonal vegetables sooner or explore foreign vegetables unsuitable for your local climate, seedling cultivation becomes indispensable. This is especially true in regions with cold climates and short growing seasons; without advance seedling cultivation, many vegetables cannot be successfully planted.
One of the most prevalent mistakes in seedling cultivation is keeping them for too long. As seedlings mature, their root systems become more extensive, necessitating more space for development. When confined to the limited space of a seedling pot, growth can be stunted, resulting in poor development or even failure to thrive. In such cases, it is often more effective to transplant them directly into the ground.
In colder areas, it's crucial not to start raising seedlings too early. Generally, for vegetables that require over four months to mature, seedlings can be started 6-8 weeks before planting them in the ground. For those maturing in 3-4 months, it’s advisable to start 4-6 weeks early, while vegetables that mature within three months can begin 2-4 weeks in advance.
Next, let’s explore the necessary steps for raising seedlings.
### Facilities Required for Seedling Raising
#### Seedling Raising Box
You can either purchase pre-made seedling boxes or construct one using wooden boards. Typically, the dimensions for the seedling box are around 30x45 cm or 45x60 cm, with a height of about 10 cm. Crucially, ensure that the box has a drainage system in place, such as holes or slits, to prevent waterlogging. Alternatively, larger flower pots can also serve this purpose.
Although plastic seedling bags or pots are readily available, you can also craft seedling pots at home. This approach not only saves money but also provides a fun activity for children and fosters creativity. An option is to use kraft paper; cut it into long strips (the width corresponds to the pot's depth) and wrap it firmly around a suitably-sized bottle. Secure the paper with strong cotton thread, then remove the bottle to reveal your homemade seedling pot, which is eco-friendly and eliminates root disturbance during transplanting.
Additionally, you can repurpose various containers like disposable paper cups, yogurt cups, or plastic bottles into seedling pots by removing the bottom and adjusting the height. The ideal height should slightly exceed the diameter, which varies depending on the vegetable type—12 cm for melons, 9 cm for eggplant and cabbage, and 6 cm for beans.
You will also need to create garden trays for the bottomless seedling pots. Construct a tray from plywood with a border of wooden strips, filling the bottom with gravel and placing the seedling pots on top. If you’re gardening on a balcony or roof, consider using plastic boxes from dried fruits as trays.
#### Seedling Soil
It's crucial not to use garden soil directly for germinating seedlings, as it tends to be overly clumpy for seeds and may harbor pathogens and pest eggs. Successfully growing seedlings in this soil can lead to illnesses such as root rot.
Seedling soil can be made at home or purchased ready-made. A simple homemade mixture includes equal parts of compost, sterilized garden soil, and sand, all of which should be screened to remove any large particles.
#### Seedling Site and Simple Greenhouse
Select a sheltered, sunny, and well-ventilated area for your seedlings that receives at least five hours of sunlight daily. The seedling area, resembling a vegetable bed, should be elevated and covered with stones and gravel to maintain dryness.
In colder springs, consider constructing two simple greenhouses—one transparent to allow sunlight and protect seedlings, and another black to store seedling boxes and pots while awaiting germination.
The greenhouse should stand about 30-40 cm high and be wide enough for easy access from both sides, with an indefinite length. You’ll need transparent plastic film, black shade netting, and bamboo strips for construction.
Each bamboo strip should be approximately 2.5 meters long, bent and inserted into the soil about 30 cm apart, then covered with plastic film and shade netting, secured with soil at the edges while ensuring ventilation at the ends.