Growing Plants from Seed
Growing plants from seed allows the home gardener to produce a large number of plants at a relatively small cost. Packets of seeds are produced by commercial seed growers and can be readily purchased from your local garden centre or supplier, seed catalogues or ordered online. The most common seeds raised for the home garden include:
Marigolds, stocks, pansies, asters, petunias and cosmos are just a few of a large variety of seeds that are easy to grow from seed for mass bedding displays.
Vegetables can be grown from seed either by planting directly in the ground (beans, peas, pumpkins etc) or in seed trays for smaller seeds (tomatoes, spinach, lettuce etc) that are later transplanted out into the garden. When planting seeds it is not necessary to use the whole packet. Make successive sowings 2-3 weeks apart to provide an ongoing supply throughout the growing season.
When planting herb seeds from packets directly into the garden, place them 3-4 times their thickness down into the soil. As seedlings emerge, thin out the weaker plants so they are appropriately spaced with room to grow.
How to Grow Plants from seed
Seeds when purchased are in their resting "dormant' stage of the life cycle and require the three essentials elements of warmth, moisture and air for germination.
If you not going to use the seed for a time after initial purchase store in a cool airy place to help ensure that the eventual percentage of seeds that germinate remains high. Most seed packets have a "use by" date printed on the outside that indicates the maximum time recommended for storage.
Purchase a supply of seed trays and mini-pots to have on hand from your garden centre. These can be used again each year so make a worthwhile investment. Check to ensure the trays have ample holes that allow for good drainage and air circulation.
A good quality seed raising mix from your local supplier is recommended for getting seedlings off to a good start. Commercially prepared seed raising mixes are formulated to help prevent seedlings being attacked by soil-borne disease or fungus.
The planting directions are often given for individual plant varieties on the outside of the seed packet. Depending on the type of plant, start seeds 4 to 8 weeks before the last frost if you plan to move them outdoors.
Nearly-fill your tray or mini-pots with seed starting mix. Sprinkle a few seeds onto the mix and cover with a little extra of the mix. Water well and cover each tray or pot with clear plastic to keep in the warmth. Once the seedlings appear uncover and keep in a sunny spot. Turn the trays or pots regularly to ensure plants have an even growth habit with straight stems. Watering with a solution of liquid plant fertilizer encourages strong root development and helps develop healthy, strong and robust plants.
Seeds that have been sown too thickly can be "thinned" by transferring to individual pots when about 7-9 cm (3-4 inches) tall. This ensures plenty of room for root development and prevents roots becoming entwined with neighbouring seedlings causing damage to the delicate root system when separating the plants for transplanting into the garden.
If you started your seedlings indoors, two weeks before you're ready to transplant, 'harden" your new seedlings by taking them outdoors for a few hours each day. When there is no longer any risk of frost take the seedlings out of their pots and plant into the garden.
Transplant seedlings when they show their first true leaf. To transplant use a dibber or small pointed stick in one hand to make the hole in the soil. Pick up the seedling by the leaf (not by its stem) and position it carefully. Gently firm the soil around the roots with the dibber.
Saving your Seeds
Perennials tend to self-seed and germinate by themselves when conditions are right. This provides an ongoing abundance of plants that often appear in unexpected places.
You can harvest your own seeds from annual plants and vegetables for replanting the following year. Collect seeds from different plants in the garden and store in named brown paper bags or envelopes until ready to use. Alternatively store in an airtight container with silica gel. Silica gel absorbs moisture and helps prevent the growth of fungi that can destroy your seeds.
Collecting your own seeds can have the advantage of growing plants not normally available from garden centres or nurseries and also the opportunity to produce a large number of plants or perhaps your own hybrid plants.