Sowing seed outdoors and indoors
Seed can be sown directly in the ground after all danger of frost is past. Work up a bed or an area with compost to enrich the soil. The soil should have a fine texture and good drainage.
Indoors, start the seed in flats or small plastic pots that are brand new, or if used, they need to be scrubbed clean and dipped in a 10% bleach solution. Prepare these by filling them with a seed-starting mix like Promix ™ which is a soilless potting medium, or make your own by combining equal parts spaghnum peat with perlite or vermiculite. Dampen this medium thoroughly before sowing seed. It should not be soaking wet. Place two or three seeds in each pot or make rows in a flat. Seeds planted in rows, rather than scattered, have fewer problems after germination because of improved air circulation. Cover the seeds lightly with a thin layer of dampened potting mix. Cover germinating flats with a plastic dome or plastic wrap to preserve moisture. Be sure to put tags in the flats so that you know what you are growing, or keep a notebook with a sketch. I make notes in my gardening journal of when I sow seed, days they germinate, when I transplant, etc.
Use sand to improve drainage.
Save money by making your own mix
Making seed-starting soil is easy, fun, and less expensive than purchasing a premade mix. First, put two parts compressed, peat-based soilless potting soil, like Fafard #2 or Metromix, in a trug or wheelbarrow. (Coir is an acceptable substitute.) Add one part clean, washed sand (sand for children’s sandboxes is ideal) to improve drainage. Add 1 tablespoon of slow-release fertilizer pellets, such as Sierra Blend or Osmocote, for every cubic foot of ingredients to provide ongoing nourishment. Mix it all together. Use packaged materials that are clean and sterile for a mix that feels light and crumbly
Tamp the soil for a firm seedbed.
A topdressing of gravel helps seeds get started
Take any plastic pot you have at hand, and fill it loosely with potting mix flush to the brim. Tamp the soil, leaving a quarter inch or so of space below the rim. Sow the entire packet of seeds in a single pot. Sow large seed (lupines, for example) directly on the soil mix, and top-dress with sterile aquarium gravel the size of BBs. Sow fine seed directly onto a topdressing of sterile aquarium gravel. Do not bury the seeds. This topdressing method keeps the soil beneath evenly moist and provides a sterile zone for the stems of germinating seeds. This minimizes damping off, a dread fungus that can cause mass seedling die-off.
Water gently and wait patiently
So as not to disturb the seed scattered in the topdressing, water the seed pots from the bottom up using any shallow basin filled with just enough water to rise to within an inch below the seed-pot rims. Let soak for 15 minutes until the soil is wet to the top. Place the seed flats in a sunny area protected from wind. If you have protracted, dry winter weather, you may have to water the seed pots a few times with a gentle spray. Be patient. Some generally require several seasons to germinate
Prick out individual seedlings
“Pricking out” is when you separate the seedlings in the pot they were sown in to individual small pots where they can grow to become full-fledged plants. Pots that are 2¼ inches square filled with a sterile potting mix are perfect for potting on a single seedling. Carefully pull the root-ball of seedlings apart, and place each individual seedling into its own pot. Protect the new seedlings from the midday summer sun with a shade cloth for a month or two to help them survive the shock of potting on. Once your seedlings have had time to expand their roots in their individual pots, they are ready to go into the ground whenever you want them.