Secure a seed starting stand with the ability to hang the fluorescent lights above the seedlings and raise and lower the height of the lights.
Fill 2-inch starter pots with seed starting mix. Smooth the top of the soil.
Sprinkle ranunculus seed generously on top of the growing mix. The seeds of this flower have a low germination rate so plant a large number of seeds. Sprinkle a thin layer of the seed starting mix on top of the seeds. Gently firm the top of the soil with your hand.
Place the 2-inch starter pots into a large shallow container. Add water to the large container until it is half way up the sides of the 2-inch pots. Let them sit in the water until the surface of the seed starting mix looks damp. Remove 2-inch pots from the water and allow them to drain thoroughly. Water using this method until the seedlings are 2- to 3-inches high.
Place the pots under the fluorescent lights so the top of the pot is about 4 inches from the bulb. Keep the pots at a temperature of 50 degrees Fahrenheit until they germinate in about 20 to 30 days.
Thin when the seedlings are about 2 inches high. Use the tip of a scissors and snip off all but the strongest plant in each 2-inch pot. Cut off the unwanted seedlings at soil level.
Raise the height of the lights as the seedlings grow to maintain a distance of about 3 to 4 inches between the tops of the plants and the light bulbs. Keep the lights on for 14 to 16 hours a day.
Begin to harden off the seedlings when daytime temperatures are in the upper 40s. Put the small ranunculus plants outdoors in the shade for a longer period each day until they are outdoors all day long. After that, move the pots into full sunlight for a longer period each day until they are in full sunlight all the time. Bring plants indoors at night or anytime frost threatens.
Plant in the garden in a location that has full sun and very well-drained soil. Space the transplants about 8- to 12-inches apart in regular, unimproved garden soil.
Water the transplants as you plant them using a hand watering can. Continue to provide ranunculus with the equivalent of 1 inch of rainfall per week.
Fertilize weekly with a water soluble fertilizer applied to individual plants with a hand watering can. Use a mixture that is half the manufacturer's recommended rate of application.
Mulch the soil in the garden bed with 2 to 4 nches of organic mulch, such as buckwheat hulls or shredded bark. Ranunculus are cool-weather perennials and prefer their roots cool but not soggy.
Mulch the roots in late fall after the foliage has died down for the winter. Put down a 6- to 12-inch layer of hay or straw to protect the roots from freezing winter temperatures.