April 14 is the AVERAGE last frost date in Knoxville. Wait until then at least to plant tender annuals. Remember to cover tender Japanese maple foliage in the event of a late frost. Japanese maple foliage always emerges before the last frost and is tender to a late cold snap.
Now is the time to prune winterberry holly and twig dogwood. Cut twig dogwood 1 to 2 feet from the ground. Prune winterberry holly only when necessary.
Prune spring-flowering shrubs (azaleas, quince, forsythia, Kerria, and Loropetalum) soon after they finish flowering, but only if they need
it. Selectively cut old or unruly branches by reaching deeply into the shrub leaving no visible stub, making the cut just above a joint.
If using a pre-emergent herbicide, be sure to apply it before spreading your mulch to prevent the sunlight from breaking it down. It also forms a more effective barrier when allowed to bond with soil particles.
After danger of frost, prune boxwood to desired shape. Cut back any perennials that may look leggy and ragged. St. Johns Wort, lavendar, rosemary.
Once daffodil foliage has turned yellow, you can mow or cut it down. If you remove it while it is still green, you decrease the amount of energy available for the bulb to store, decreasing flower size next year.
