Crocus, Lenten Roses, Violets, and Daffodils are all early bloomers and might start to emerge as early as February. However, these early blooming plants can give you a false sense of spring and winter snows might go as late as May.
Early spring blooms are dangerous for a majority of fruit trees and flowering perennials. While some shade trees and ornamentals can survive freezing temperatures during flowering, freezing temperatures will cause blossoms to fall from fruit & ornamental trees terminating fruit & flower production for the season.
Even though other plants might start to green up, as protection from Ohio’s ever-changing spring weather, a majority of perennials won’t start to green up until both soil and air temperatures rise about 60 degrees. Hibiscus, Sugar Maples, and Crape Myrtle shrubs are all perennials that typically are late to come out of winter dormancy in the spring. Make sure you give these perennials plenty of time to green up and grow before deciding they are dead.
The Butterfly bush is usually one of the last perennials to green up and bloom. This pollinator-attracting shrub can sometimes go as late as mid-summer to early fall to fully bloom. While waiting for new spring growth and flowers, after the frost-free date, cut back any dead limbs and branches.
Do not prematurely remove any late sleeping perennials. You can test their dormancy by scratching the bark looking for green. The stems of the plant should be pliable and firm and will have a green cast on the inside if they are still alive.
To keep your garden looking fresh and alive while waiting for your perennials to waken up, plant early season annuals like snapdragons, pansies, and violets or fill holes with ornamental Cole vegetables like cabbage and kale.