By: Lee Gray, Sevier Co. Master Gardener
IMPORTANT – Begin to prepare the plants that you are going to donate for the annual Master Gardener Plant Sale on April 21st.
Plants in Flower
Crabapple, Carolina Silverbell, Dogwood, Redbud, Flowering Cherry, Viburnum, Pearlbush, Lilac, Carolina Rhododendron, Sweet Shrub, Piedmont Azalea, Loropetalum, Exbury Azalea, Spirea, Pieris, Evergreen Azaleas, Kerria (Easter Rose), Drooping Leucothoe, Weigela, Wisteria, Periwinkle, Ajuga, Candytuft, Violets, Columbine, Trillium, Flags (Dwarf Iris), Bloodroot, Bleeding Heart, Jack-In-The-Pulpit, Anemone and Siberian Squill.
What to Fertilize & Spray
- Fertilize shrubs if not done in March.
- Once you can determine whether your fruit trees have any fruit, you can decide how much fertilizer to give them.
What to Plant
- Many gardeners prefer to transplant azaleas in April so they can group the
plants according to their flower color.
- The following vegetables can be planted this month: beets, cabbage, Chinese
cabbage, Swiss chard, broccoli, cauliflower, onion, and potatoes.
- Divide overgrown clumps of Hosta now that you can see the leaves unfurling above ground.
- Repot houseplants you plan to move outdoors. Their roots will need more room as they grow rapidly in the sun.
What to Prune
- Prune spring-flowering plants like azalea, lilac, forsythia, spirea, and
weigela after the flowers fade.
- Prune berry producing shrubs like holly and pyracantha while in flower to
prevent complete removal of all of this season’s berries.
- If needed, trim spring flowering trees like Bradford pear, flowering cherry and redbud.
- Cut out any winter damage that may have occurred this year.
- Last chance to prune roses to approximately one half their present size.
- Observe the following landscape shrubs for the following insect pests: azalea-lacebug, boxwood-leaf miner, euonymus-scale, hemlock and juniper-spruce mites and spray as needed. Hybrid rhododendron should be sprayed for borers annually.
- Spray iris beds for iris borers.
- Treat broccoli, cabbage and cauliflower for worms as needed. An organic product containing BT is recommended.
- Spray your squash plants at first bloom near the base of the stem to control squash vine borer. Continue through June 1 and use only the recommended insecticide.
- Spray your apple and pear trees with streptomycin for control of fireblight while the trees are in bloom. Apply two times, once at early bloom and a second treatment at full bloom. In wet spring weather consider a third application.
- Start a fungicide spray program for your bunch grapes this month. Follow
with weekly sprays.
- Continue with the rose spray program.
- Begin weekly tree fruit sprays after flower petals fall.
- With the exception of borer insects, always scout your landscape plants before spraying. Pests may not be present.
- Maintain mowing height of fescue and bluegrass at 3 inches.
- Do NOT fertilize cool season lawns such as tall fescue or Kentucky bluegrass anymore this spring. April is the first month to fertilize zoysia lawns.
- This is a good time to layer new plants by lowering a branch of your favorite shrubs and covering it with soil and a stone.
- Make sure you clean and disinfect all tools to protect from spreading disease. Start your gardening season off disease free. This is worth noting again for those who have not started their spring cleaning.
- Mulch all of your landscape plants as needed. Pine needles, cypress mulch and pine bark are good mulches. Pine bark, cypress mulch, pine needles and hardwood bark are good mulches.
- Prepare labels for all new plants and keep records on how well they perform.
- Special thanks to the following websites for the material listed above.
- NC Extension – https://henderson.ces.ncsu.edu
- Walter Reeves – http://www.walterreeves.com/