Ranunculus is winter-hardy in U.S. Department of Agriculture plant hardiness zones 8 to 11, where the lowest winter temperatures average at least 10 degrees Fahrenheit. It is planted in the fall and blooms in the spring. In zone 7, your winters are a bit too cold for a normal planting. Fortunately, you can still plant ranunculus in your climate and with proper timing, you'll also be able to take pleasure in its colorful and rose-like blooms just like Southern gardeners.
Plant your ranunculus flowers in zone 7 during the spring, when the last frost of the season occurs within a week or two. This often happens around mid-April.
Amend the soil to create a planting bed that is well-draining and rich in nutrients. Turn over the top 6 inches with your garden rake or hoe, and mix in about 2 or 3 inches of compost. If the ground is frozen when you do this step, then wait for a week and try again.
Plant the ranunculus tubers just below the soil's surface with a trowel and apply ½ to 1 inch of water. The eyes (buds) should be facing up toward the top of the holes. Space multiple ranunculus 4 to 6 inches apart. Expect your ranunculus tubers to bloom later in zone 7 (usually in June or July) than they do in warmer zones.