Position: Your propagation tray should be located in a well lit area with good ventilation (on very hot days move the tray to a semishaded position). Many seeds of course, can be planted directly into the ground.
Selection: When deciding which seeds to use, a major factor governing success or failure is the 'viability' of the seed. Do not use stale seeds. This can be avoided by adhering to the use by date printed on most seed packets. Fresh seeds can give up to twice the germination rate of seeds kept for some months. Planting seasons are also printed on the packet.
Preparation of Materials: The right materials and attention to hygiene are the keys to the 'seed-raisers' science. Pots and containers should be cleaned thoroughly before use. Soils caked to the side of the pot can harbour diseases. Washing with disinfectant and a few drops of washing-up liquid or garden cleanser should do the trick. Rinse over all containers with clean water before use with fresh soil.
Pots and Seed Mix: Seed sowing mix is a matter of choice. It should be free draining, yet capable of holding sufficient moisture to allow the seeds to germinate. Never use conventional potting mixes for seed sowing as many contain levels of fertiliser which can burn sensitive young roots or will cause seedlings to grow abnormally quickly.
Choosing the Right Container: There are a bewildering array of pots, trays, tubes and containers suitable for use. If you are unsure which size to go for, it is better to use a pot that is too large than be tempted to sow too thickly. Overcrowded seedlings will be thin and weak. Large seeds can be sown individually or spaced equally in trays. When preparing the mix, the idea is to produce conditions as uniform as possible to ensure that the maximum amount of seed germinates. Fill the container loosely with soil until it is slightly proud of the rim. Scrape off the excess with a piece of wood to leave a level surface. The seed mix should be compressed so that a gap of about 25mm is left below the rim of the container.
Seed Sowing Technique: Often the most critical stage of the whole process is the act of transferring seed from the packet onto the seed mix. Have all your containers filled and prepared and other equipment ready and waiting before opening the seed packet. Always read the instructions on the packet first. They will usually tell you how and when to sow as well as highlighting temperatures required for germination. Certain types of seed, such as many species of Australian native plants, may need special preparation before sowing - such as soaking in hot water for a period of time - so only open the packet when you are ready to use the seeds.
Watering: When the seeds have been sown they should be watered immediately. Continue to water sparingly until germination. As the plants grow stronger, thorough but less frequent watering is required.
Information Provided by Plants Plus and Nurserymens Brand.