Native to North America, flowers in the Rudbeckia genus (Rudbeckia spp.) are commonly referred to as black-eyed Susans and coneflowers. The Tiger Eye gloriosa daisy (Rudbeckia "Tiger Eye Gold") is a registered hybrid that grows in U.S. Department of Agriculture plant hardiness zones 3 through 9. The 4-inch flowers feature a bright gold color and layers of petals in a semi-double flower form. This rudbeckia variety features strong branching, rapid growth and uniform flowering throughout the plant. You can sometimes find transplants in nurseries or order seeds and start your own plants indoors eight weeks before the last expected frost.
Prepare a potting mixture of equal parts sphagnum peat, compost and coarse sand. Fill plastic cell packs or a seedling tray with the potting mixture, leaving about 1/4 inch to the top edge of the container. Water the soil so it is evenly moist before planting the seeds.
Sow two seeds in each cell of a cell pack. Push down on the seeds gently with your finger to ensure good contact between the soil and seeds but do not cover the seeds with potting soil. Place the cell packs on a tray to catch any moisture as it drains from the soil.
Place the seed trays in your refrigerator or in a cool location, such as a garage, for about four weeks; this cold stratification period aids in germination.
Move the cell packs to a location with temperatures of about 70 degrees Fahrenheit for a period of one to two weeks. Move the trays to a window that receives full sun and thin the plants when they develop two leaf sets, leaving the strongest plant in each cell. Add water as needed to maintain moisture in the soil.
Set the plants outdoors for a few hours each day for about two weeks to harden them off before transplanting outdoors. Place the plants in shade for about four hours the first day; gradually increase the amount of time and sunlight over the two-week period.
Work organic matter, such as compost, manure, peat moss and sand, into the soil of the planting site to improve drainage and soil structure. Rudbeckias adapt to most soil types, but they do best in fertile soil with good drainage. The planting site should be in full sun.
Plant the seedlings to the same depth as the root ball so the top of the root ball rests even with the surrounding soil. Space each plant 18 to 30 inches apart to grow them as perennials.
Water the plants deeply immediately after planting, ensuring that the entire root ball is evenly moist. Water the rudbeckias about once weekly to keep the root zone moist; more frequent watering is required during hot weather.
Add a 2- to 3-inch layer of shredded bark mulch around plants to help prevent weeds and retain moisture in the soil. Alternatively, you can mulch with a mixture of compost and manure as an organic alternative to chemical fertilizers.
Deadhead the plants as flower blossoms expire to keep the plant producing new flowers. Pull the dead flowers off by hand or cut just below the flower head with a pair of bypass pruners. Additionally, you can prune away any dead leaves to keep the plant looking neat.
Things You Will Need
- Sphagnum peat moss
- Coarse sand
- Cell packs
- Digging tools
- Organic matter
- Bypass pruners
- You can sow the seeds directly in the ground, if desired, but starting seeds indoors allows you to enjoy mature plants more quickly. Broadcast seeds over the flower bed and gently press them into the soil. Thin the developing plants as they grow to avoid overcrowding.