Snapdragons provide summer-long colour to beds, borders and pots. Available in every colour but true blue, each plant produces spikes of flowers. When pinched, the flower opens and resembles the mouth of a dragon. The flower snaps shut when released. Snapdragons range in height from just a few inches to more than 2 feet tall, depending on the variety. Planting from seed allows you to mass plant these attractive annuals without the need for purchasing seedlings in large quantities.
Fill a seed-starting flat with a sterile, well-drained potting mix. Water the mix until it is evenly moist throughout.
Sow the snapdragon seeds on the soil surface in rows. Plant approximately two seeds per inch and space rows 2 inches apart. Cover the seeds with a 1/8-inch layer of vermiculite or potting mix. Vermiculite is a fine-textured, lightweight mineral readily available at garden centres.
Cover the flat with a sheet of cling film. Set the flat in a warm, 65-degree Fahrenheit room to germinate. Some snapdragon varieties need light to germinate, which is indicated on the seed packet.
Remove the plastic once seedlings emerge, approximately five to 10 days after sowing. Move the flats to an area that receives full sunlight.
Water the potting mix when the surface begins to feel dry. Apply a balanced, soluble fertiliser at half the label recommended amount every two to three weeks.
Start snapdragon seeds indoors 10 weeks before the last expected spring frost in your area. Transplant outside after all frost danger is past. Transplant the seedlings to individual pots or cell packs when they are 2 to 3 inches tall.