When a seed first begins to grow, it is germinating. Seeds are germinated in a growing medium, such as perlite. Several factors are involved in this process. First, the seed must be active–and alive–and not in dormancy. Most seeds have a specific temperature range that must be achieved.
Moisture and oxygen must be present. And, for some seeds, specified levels of light or darkness must be met. Check the specifications of seeds to see their germination requirements.
The first two leaves that sprout from a seed are called the seed leaves, or cotyledons. These are not the true leaves of a plant.The seed develops these first leaves to serve as a starting food source for the young, developing plant.
The seed develops these first leaves to serve as a starting food source for the young, developing plant.
Soil is never used in hydroponic growing. Some systems have the ability to support the growing plants, allowing the bare roots to have maximum exposure to the nutrient solution. In other systems, the roots are supported by a growing medium.
Some types of media also aid in moisture and nutrient retention. Different media are better suited to specific plants and systems. It is best to research all of your options and to get some recommendations for systems and media before making investing in or building an operation.
Popular growing media include:
Coco coir is a relatively new growing medium that gives the experience of growing in soil, but many of the benefits of growing in hydro (such as faster growth and bigger harvests).
Soilless gardening is called hydroponics and it’s been around for thousands of years. The essential ingredient is an oxygenated mineral-nutrient solution that’s circulated through plants’ roots.
Expanded clay rock is an incredibly resourceful growing material, is derived from clay. Clay itself is renewable and plentiful making Expanded Clay Rock a premium growing medium due to its ecologically sustainable quality.
Perlite. Volcanic glass is mined from lava flows and heated in furnaces to a high temperature, causing the small amount of moisture inside to expand. This converts the hard glass into small, sponge-like kernels.
Rockwool. This is created by melting rock at a high temperature and then spinning it into fibers.
There are a number of other materials that can (and are) used as growing media. Hydroponic gardeners tend to be an innovative and experimental group.
Think of a plant as a well-run factory that takes delivery of raw materials and manufactures the most wondrous products. Just as a factory requires a reliable energy source to turn the wheels of its machinery, plants need an energy source in order to grow.
Usually, natural sunlight is used for this important job. However, during the shorter and darker days of winter, many growers use artificial lights to increase the intensity of light (for photosynthesis) or to expand the daylight length. While the sun radiates the full spectrum (wavelength or color of light) suitable for plant life, different types of artificial lighting are selected for specific plant varieties and optimum plant growth characteristics.
Different groups of plants respond in physically different ways to various wavelengths of radiation. Light plays an extremely important role in the production of plant material. The lack of light is the main inhibiting factor in plant growth. If you reduce the light
by 10 percent, you also reduce crop performance by 10 percent.
Light transmission should be your major consideration when purchasing a growing structure for a protected crop. Glass is still the preferred material for covering greenhouses because, unlike plastic films and sheeting, its light transmission ability is indefinitely maintained.
No gardener can achieve good results without adequate light. If you intend to grow indoors, avail yourself of some of the reading material that has been published on this subject. If you are having trouble growing good plants, then light is the first factor to question.